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TE 60-A36

Original operating instructions

Information about the documentation

About this documentation

  • Read this documentation before initial operation or use. This is a prerequisite for safe, trouble-free handling and use of the product.
  • Observe the safety instructions and warnings in this documentation and on the product.
  • Always keep the operating instructions with the product and make sure that the operating instructions are with the product when it is given to other persons.

Explanation of symbols used

Warnings

Warnings alert persons to hazards that occur when handling or using the product. The following signal words are used:
DANGER
DANGER !
  • Draws attention to imminent danger that will lead to serious personal injury or fatality.
WARNING
WARNING !
  • Draws attention to a potential threat of danger that can lead to serious injury or fatality.
CAUTION
CAUTION !
  • Draws attention to a potentially dangerous situation that could lead to personal injury or damage to the equipment or other property.

Symbols in the documentation

The following symbols are used in this document:
Image alternative Read the operating instructions before use.
Image alternative Instructions for use and other useful information
Image alternative Dealing with recyclable materials
Image alternative Do not dispose of electric equipment and batteries as household waste

Symbols in the illustrations

The following symbols are used in illustrations:
Image alternative These numbers refer to the corresponding illustrations found at the beginning of these operating instructions
Image alternative The numbering reflects the sequence of operations shown in the illustrations and may deviate from the steps described in the text
Image alternative Item reference numbers are used in the overview illustrations and refer to the numbers used in the product overview section
Image alternative This symbol is intended to draw special attention to certain points when handling the product.

Product-dependent symbols

Symbols on the product

The following symbols are used on the product:
Image alternative Drilling with hammering action (hammer drilling)
Image alternative Chiseling
Image alternative Chisel positioning
Image alternative Protection class II (double-insulated)
Image alternative Revolutions per minute
Image alternative Rated speed under no load
Image alternative Diameter
Image alternative Direct current (DC)
Image alternative Li-ion battery
Image alternative Hilti Li-ion battery type series used. Observe the information given in the section headed Intended use .
Image alternative The product supports wireless data transmission compatible with iOS and Android platforms.
Image alternative Never use the battery as a striking tool.
Image alternative Do not drop the battery. Never use a battery that has suffered an impact or is damaged in any other way.

Switching on and off

Symbols
Image alternative Product is switched on
Image alternative Product is switched off

Product information

Image alternative products are designed for professional users and only trained, authorized personnel are permitted to operate, service and maintain the products. This personnel must be specifically informed about the possible hazards. The product and its ancillary equipment can present hazards if used incorrectly by untrained personnel or if used not in accordance with the intended use.
The type designation and serial number are printed on the rating plate.
  • Write down the serial number in the table below. You will be required to state the product details when contacting Hilti Service or your local Hilti organization to inquire about the product.
    Product information
    Combihammer
    TE 60‑A36
    Generation
    04
    Serial no.

Declaration of conformity

Image alternative
We declare, on our sole responsibility, that the product described here complies with the applicable directives and standards. A copy of the declaration issued by the certification department can be found at the end of this documentation.
The technical documentation is filed here:
Hilti Entwicklungsgesellschaft mbH | Tool Certification | Hiltistrasse 6 | 86916 Kaufering, Germany

Safety

General power tool safety warnings

Image alternative WARNING Read all safety warnings, instructions, illustrations and specifications provided with this power tool. Failure to follow all instructions listed below may result in electric shock, fire and/or serious injury.
Save all warnings and instructions for future reference.
The term "power tool" in the warnings refers to your mains-operated (corded) power tool or battery-operated (cordless) power tool.
Work area safety
  • Keep work area clean and well lit. Cluttered or dark areas invite accidents.
  • Do not operate power tools in explosive atmospheres, such as in the presence of flammable liquids, gases or dust. Power tools create sparks which may ignite the dust or fumes.
  • Keep children and bystanders away while operating a power tool. Distractions can cause you to lose control.
Electrical safety
  • Power tool plugs must match the outlet. Never modify the plug in any way. Do not use any adapter plugs with earthed (grounded) power tools. Unmodified plugs and matching outlets will reduce risk of electric shock.
  • Avoid body contact with earthed or grounded surfaces, such as pipes, radiators, ranges and refrigerators. There is an increased risk of electric shock if your body is earthed or grounded.
  • Do not expose power tools to rain or wet conditions. Water entering a power tool will increase the risk of electric shock.
  • Do not abuse the cord. Never use the cord for carrying, pulling or unplugging the power tool. Keep cord away from heat, oil, sharp edges or moving parts. Damaged or entangled cords increase the risk of electric shock.
  • When operating a power tool outdoors, use an extension cord suitable for outdoor use. Use of a cord suitable for outdoor use reduces the risk of electric shock.
  • If operating a power tool in a damp location is unavoidable, use a residual current device (RCD) protected supply. Use of an RCD reduces the risk of electric shock.
Personal safety
  • Stay alert, watch what you are doing and use common sense when operating a power tool. Do not use a power tool while you are tired or under the influence of drugs, alcohol or medication. A moment of inattention while operating power tools may result in serious personal injury.
  • Use personal protective equipment. Always wear eye protection. Protective equipment such as a dust mask, non-skid safety shoes, hard hat or hearing protection used for appropriate conditions will reduce personal injuries.
  • Prevent unintentional starting. Ensure the switch is in the off-position before connecting to power source and/or battery pack, picking up or carrying the tool. Carrying power tools with your finger on the switch or energising power tools that have the switch on invites accidents.
  • Remove any adjusting key or wrench before turning the power tool on. A wrench or a key left attached to a rotating part of the power tool may result in personal injury.
  • Do not overreach. Keep proper footing and balance at all times. This enables better control of the power tool in unexpected situations.
  • Dress properly. Do not wear loose clothing or jewellery. Keep your hair and clothing away from moving parts. Loose clothes, jewellery or long hair can be caught in moving parts.
  • If devices are provided for the connection of dust extraction and collection facilities, ensure these are connected and properly used. Use of dust collection can reduce dust-related hazards.
  • Do not let familiarity gained from frequent use of tools allow you to become complacent and ignore tool safety principles. A careless action can cause severe injury within a fraction of a second.
Power tool use and care
  • Do not force the power tool. Use the correct power tool for your application. The correct power tool will do the job better and safer at the rate for which it was designed.
  • Do not use the power tool if the switch does not turn it on and off. Any power tool that cannot be controlled with the switch is dangerous and must be repaired.
  • Disconnect the plug from the power source and/or remove the battery pack, if detachable, from the power tool before making any adjustments, changing accessories, or storing power tools. Such preventive safety measures reduce the risk of starting the power tool accidentally.
  • Store idle power tools out of the reach of children and do not allow persons unfamiliar with the power tool or these instructions to operate the power tool. Power tools are dangerous in the hands of untrained users.
  • Maintain power tools and accessories. Check for misalignment or binding of moving parts, breakage of parts and any other condition that may affect the power tool’s operation. If damaged, have the power tool repaired before use. Many accidents are caused by poorly maintained power tools.
  • Keep cutting tools sharp and clean. Properly maintained cutting tools with sharp cutting edges are less likely to bind and are easier to control.
  • Use the power tool, accessories and tool bits etc. in accordance with these instructions, taking into account the working conditions and the work to be performed. Use of the power tool for operations different from those intended could result in a hazardous situation.
  • Keep handles and grasping surfaces dry, clean and free from oil and grease. Slippery handles and grasping surfaces do not allow for safe handling and control of the tool in unexpected situations.
Battery tool use and care
  • Recharge only with the charger specified by the manufacturer. A charger that is suitable for one type of battery pack may create a risk of fire when used with another battery pack.
  • Use power tools only with specifically designated battery packs. Use of any other battery packs may create a risk of injury and fire.
  • When battery pack is not in use, keep it away from other metal objects, like paper clips, coins, keys, nails, screws or other small metal objects, that can make a connection from one terminal to another. Shorting the battery terminals together may cause burns or a fire.
  • Under abusive conditions, liquid may be ejected from the battery; avoid contact. If contact accidentally occurs, flush with water. If liquid contacts eyes, additionally seek medical help. Liquid ejected from the battery may cause irritation or burns.
  • Do not use a battery pack or tool that is damaged or modified. Damaged or modified batteries may exhibit unpredictable behaviour resulting in fire, explosion or risk of injury.
  • Do not expose a battery pack or tool to fire or excessive temperature. Exposure to fire or temperature above 130° C (265 °F) may cause explosion.
  • Follow all charging instructions and do not charge the battery pack or tool outside the temperature range specified in the instructions. Charging improperly or at temperatures outside the specified range may damage the battery and increase the risk of fire.
Service
  • Have your power tool serviced by a qualified repair person using only identical replacement parts. This will ensure that the safety of the power tool is maintained.
  • Never service damaged battery packs. Service of battery packs should only be performed by the manufacturer or authorized service providers.

Hammer safety warnings

  • Wear ear protectors. Exposure to noise can cause hearing loss.
  • Use auxiliary handles, if supplied with the tool. Loss of control can cause personal injury.
  • Hold power tool by insulated gripping surfaces, when performing an operation where the cutting accessory may contact hidden wiring. . Cutting accessory contacting a "live" wire may make exposed metal parts of the power tool "live" and could give the operator an electric shock.

Additional safety instructions for rotary hammer

Personal safety
  • Use the product only when it is in technically faultless condition.
  • Never tamper with or modify the power tool in any way.
  • Use the auxiliary grips supplied with the tool. Loss of control can cause personal injury.
  • Apply appropriate safety measures at the opposite side of the workpiece in work that involves breaking through. Parts breaking away could fall out and / or fall down causing injury to other persons.
  • Always hold the power tool with both hands on the grips provided. Keep the grips clean and dry.
  • Hold the power tool by the insulated gripping surfaces when performing work in which the accessory tool might come into contact with concealed wiring. If the accessory tool comes into contact with a live wire, metal parts of the power tool can also become live, resulting in an electric shock.
  • Avoid touching rotating parts – risk of injury!
  • Wear suitable protective glasses, a hard hat, ear defenders, protective gloves and light respiratory protection while using the power tool.
  • Wear protective gloves also when changing the accessory tool. Touching the accessory tool presents a risk of injury (cuts or burns).
  • Wear eye protection. Flying fragments present a risk of injury to the body and eyes.
  • Before starting work, check the hazard class of the dust that will be produced when working. Use an industrial vacuum cleaner with an officially approved protection class in compliance with the locally applicable dust protection regulations. Dust from materials such as lead-based paint, certain types of wood and concrete/masonry/stone containing quartz, minerals or metal can be harmful to health.
  • Make sure that the workplace is well ventilated and, where necessary, wear a respirator appropriate for the type of dust generated. Contact with or inhalation of the dust can cause allergic reactions and/or respiratory or other diseases to the operator or bystanders. Certain kinds of dust such as oakwood and beechwood dust are classified as carcinogenic, especially in conjunction with additives for wood conditioning (chromate, wood preservative). Only specialists are permitted to handle material containing asbestos.
  • Take breaks and do physical exercises to improve the blood circulation in your fingers. Exposure to vibration during long periods of work can lead to disorders of the blood vessels and nervous system in the fingers, hands and wrists.
Electrical safety
  • Before beginning work, check the working area for concealed electric cables, gas pipes and water pipes. External metal parts of the power tool can become live, presenting a risk of electric shock, if you accidentally damage an electric cable.
Power tool use and care
  • Immediately switch off the power tool if the accessory tool jams. The power tool might twist off-line.
  • Wait until the power tool stops completely before you lay it down.

Description

Product overview

Image alternative
  1. Chuck
  2. Depth gauge adjustment (accessory)
  3. Depth gauge (accessory)
  4. Function selector switch
  5. Lockbutton for sustained operation (chiseling only)
  6. Control switch
  7. Charge-status and fault indicator (Li-ion battery)
  8. Release buttons (also used to activate the charge status indicator)
  9. Battery
  10. Side handle
  11. On/off switch
  12. Button for half power
  13. Half-power indicator
  14. Service indicator
  15. ON/OFF indicator

Intended use

The product described is an electrically powered combihammer with pneumatic hammering mechanism. It is designed for drilling in concrete, masonry, wood and metal. The product can also be used for light- to medium-duty chiseling on masonry and surface finishing work on concrete.

  • Use only Hilti Li-ion batteries from the B 36 series with this product.
  • Use only the Hilti battery chargers from the C4/36 series for these batteries.

Possible misuse

  • This product is not suitable for working on hazardous materials.
  • This product is not suitable for working in a damp environment.

Undercut anchors

The product is suitable for setting undercut anchors. Use only suitable setting tools.
Detailed information on this topic can be obtained at your local Hilti Center.

ATC

The product is equipped with the ATC (Active Torque Control) quick-acting electronic cut-out.
If the accessory tool sticks or stalls, the product will suddenly pivot about its own axis in the opposite direction. ATC detects this sudden pivoting movement of the product and switches the product off immediately.
For ATC to function correctly, the product must be free to pivot.
After an ATC cut-out, switch the product off and then on again.

Active Vibration Reduction

The tool is equipped with an Active Vibration Reduction (AVR) system which reduces vibration noticeably.

Quick-release chuck (accessory)

The quick-release chuck makes changing accessory tools a quick operation with no additional tools needed. It is suitable for accessory tools with cylindrical or hexagonal shank used in the "With hammering action Image alternative" mode.

Service indicator

The product is equipped with a service indicator LED.

MMI

Status
Meaning
The Service indicator lights up.
Servicing is due.
The Service indicator flashes.
Have the product repaired by Hilti Service.
The ON/OFF indicator lights up.
The product is switched on
The ON/OFF indicator flashes.
The product is switched off because of a transient fault.
The ON/OFF indicator is off.
The product is switched off.
The Half power indicator lights up.
The product is working at half power.
The Half power indicator is off.
The product is working at full power.

Lithium‑ion battery status display

The Li-ion battery state of charge and malfunctions of the power tool are indicated by the display on the Li‑ion battery. The Li‑ion battery state of charge is displayed after pressing one of the two battery release buttons.
Status
Meaning
4 LEDs light.
State of charge: 75 % to 100 %
3 LEDs light.
State of charge: 50 % to 75 %
2 LEDs light.
State of charge: 25 % to 50 %
1 LED lights.
State of charge: 10 % to 25 %
1 LED blinks.
State of charge: < 10 %
1 LED flashes, the product is not in working order.
The battery has overheated or is completely discharged.
4 LEDs flash, the product is not in working order.
The power tool is overloaded or has overheated.
Battery state of charge cannot be displayed while the control switch is pressed and for up to 5 seconds after releasing the control switch.
If the battery display LEDs blink, please observe the instructions given in the Troubleshooting section.

Items supplied

Combihammer, side handle, operating instructions.
Other system products approved for use with this product can be found at your local Hilti Store or online at: www.hilti.group | USA: www.hilti.com

Technical data


TE 60-A36
Rated voltage
36 V
Weight
8.1 kg
(17.9 lb)
Single impact energy
8.1 J
Hammer drill bits, Ø
1/2 in …1 9/16 in
Breach bits, Ø
1 9/16 in …3 1/8 in
Percussion core bits, Ø
1 3/4 in …4 in
PCM diamond core bits, Ø
1 1/2 in …4 in
Drill bits for metal, Ø
1/4 in …1/2 in
Drill bits for wood, Ø
13/32 in …1 1/4 in
Chuck
TE‑Y

Operation

Preparations at the workplace

Switch the product off or remove the battery before making adjustments or changing accessories.
Observe the safety instructions and warnings in this documentation and on the product.

Removing the battery

Image alternative
  1. Press the release buttons on the battery.
  2. Pull the battery out toward the rear.

Fitting the side handle

CAUTION
Risk of injury! Loss of control over the combihammer.
  • Check that the side handle is fitted correctly and tightened securely. Check that the clamping band is engaged in the groove provided on the tool.
CAUTION
Risk of injury. The depth gauge, if fitted but not used, might hinder the operator.
  • Remove the depth gauge from the product.
Image alternative
  1. Release the side handle clamping band by turning the handle grip.
  2. Slide the side handle clamping band over the chuck from the front and into the recess provided.
  3. Set the side handle to the desired position.
  4. Tighten the side handle clamping band by turning the handle grip.

Fitting the depth gauge (optional)

Image alternative
  1. Release the side handle clamping band by turning the handle grip.
  2. Slide the depth gauge from the front into the 2 guide holes provided.
  3. Secure the side handle by turning the knob until the clamping band is tight.

Setting the power level

After the battery is inserted, the product is always set by default to full power.
  1. Press the "button for half power". The product runs at half power.
    • The "half power indicator" lights up.
  2. Press the "button for half power" again. The product runs at full power.
    • The "half power indicator" goes out.

Inserting / removing the accessory tool

DANGER
Risk of fire! Risk of contact between the hot accessory tool and highly inflammable materials.
  • Do not lay the hot accessory tool down on highly inflammable materials.
CAUTION
Risk of injury! The accessory tool gets hot during use.
  • Wear protective gloves when changing the accessory tool.
  • Do not place the hot accessory tool on readily flammable materials.
The use of unsuitable grease can cause damage to the product. Use only genuine Hilti grease.
Image alternative
  1. Apply a little grease to the connection end of the accessory tool.
    • Use only genuine Hilti grease. Using the wrong grease can result in damage to the product.
  2. Push the accessory tool into the chuck as far as it will go (until it engages).
  3. After fitting the accessory tool, grip it and pull it in order to check that it is securely engaged.
    • The product is ready for use.
  4. Pull the chuck ring back as far as it will go and remove the accessory tool.

Inserting the battery

WARNING
Electrical hazard! Risk of short circuiting.
  • Before inserting the battery, check to ensure that the battery terminals and the contacts on the combihammer are free from foreign objects.
WARNING
Risk of injury! Hazard presented by a falling battery.
  • A falling battery may present a risk of injury to yourself and others. Check that the battery is securely seated in the combihammer.
Image alternative
  1. Push the battery into the battery holder until it engages with an audible click.
  2. Check that the battery is seated securely.

Types of work

CAUTION
Risk of injury! Loss of control over the combihammer.
  • Check that the side handle is fitted correctly and tightened securely. Check that the clamping band is engaged in the groove provided on the tool.
Observe the safety instructions and warnings in this documentation and on the product.

Drilling with hammering action (hammer drilling)

  1. Set the function selector switch to this symbol: Image alternative.
  2. Set the desired power level.
  3. Press the drill bit against the work surface.
  4. Press the control switch.
    • The product starts.

Drilling without hammer action

Drilling without hammering action is possible when accessory tools with a special connection end are used. Accessory tools of this kind are available from Hilti . Alternatively, when the keyless quick-release chuck is fitted, smooth-shank drill bits for wood or steel, for example, can be used to drill without hammering.
  • Set the function selector switch to this symbol: Image alternative.

Chisel positioning

CAUTION
Risk of injury! Loss of control over the chisel direction.
  • Do not operate the tool when the selector switch is set to “Chisel positioning”. Turn the function selector switch until it engages in the “Chiseling” position.
The chisel can be set to 24 different positions (in 15° increments). This ensures that flat chisels and shaped chisels can always be set to the optimum working position.
Image alternative
  1. Set the function selector switch to the "Chisel positioning” position Image alternative.
  2. Turn the chisel to the desired position.
  3. Set the function selector switch to this symbol: Image alternative until it engages.
    • The product is ready for use.

Chiseling

  • Set the function selector switch to the "Chiseling" position Image alternative.

Switch sustained operation on and off

When chiseling, the control switch can be locked in the “on” position.
Image alternative
  1. Push the lockbutton for continuous operation forward.
  2. Press the control switch fully.
    • The product then runs in sustained operating mode.
  3. Push the lockbutton for continuous operation back.
    • The product switches off.

Care and maintenance

WARNING
Risk of injury with battery inserted !
  • Always remove the battery before carrying out care and maintenance tasks!
Care and maintenance of the tool
  • Carefully remove stubborn dirt.
  • Clean the air vents carefully with a dry brush.
  • Use only a slightly damp cloth to clean the casing. Do not use cleaning agents containing silicone as these can attack the plastic parts.
Care of the Li‑ion batteries
  • Keep the battery free from oil and grease.
  • Use only a slightly damp cloth to clean the casing. Do not use cleaning agents containing silicone as these may attack the plastic parts.
  • Avoid ingress of moisture.
Maintenance
  • Check all visible parts and controls for signs of damage at regular intervals and make sure that they all function correctly.
  • Do not operate the product if signs of damage are found or if parts malfunction. Have it repaired immediately by Hilti Service.
  • After cleaning and maintenance, fit all guards or protective devices and check that they function correctly.
To help ensure safe and reliable operation, use only genuine Hilti spare parts and consumables. Spare parts, consumables and accessories approved by Hilti for use with the product can be found at your local Hilti Store or online at: www.hilti.group .

Transport and storage of cordless tools

Transport
    CAUTION
    Accidental starting during transport !
  • Always transport your products with the batteries removed!
  • Remove the battery.
  • Never transport batteries in bulk form (loose, unprotected).
  • Check the tool and batteries for damage before use after long periods of transport.
Storage
    CAUTION
    Accidental damage caused by defective or leaking batteries !
  • Always store your products with the batteries removed!
  • Store the tool and batteries in a place that is as cool and dry as possible.
  • Never store batteries in direct sunlight, on heating units or behind a window pane.
  • Store the tool and batteries in a place where they cannot be accessed by children or unauthorized persons.
  • Check the tool and batteries for damage before use after long periods of storage.

Troubleshooting

If the trouble you are experiencing is not listed in this table or you are unable to remedy the problem by yourself, please contact Hilti Service.

Troubleshooting

Trouble or fault
Possible cause
Action to be taken
No hammering action.
The product is too cold.
  • Bring the product into contact with the working surface, switch it on and allow it to idle. If necessary, repeat the procedure until the hammering mechanism begins to operate.
The battery runs down more quickly than usual.
Battery condition is not optimal.
  • Replace the battery.
The battery does not engage with an audible "double click".
The retaining lugs on the battery are dirty.
  • Clean the retaining lugs and refit the battery.
The drive spindle does not rotate.
The permissible operating temperature of the product’s electronics has been exceeded.
    The ON/OFF indicator flashes.
  • Allow the product to cool down.
The battery is discharged.
  • Change the battery and charge the empty battery.
Product switches off automatically.
The overload protection system is active.
    The ON/OFF indicator flashes.
  • Release the control switch. Allow the product to cool down. Press the control switch again. Reduce the load on the tool.
Product switches off if drill bit jams.
The electronic safety shut-down has tripped to avoid further jamming.
  • Release the drill bit.
The combihammer or the battery gets very hot.
Electrical fault.
  • Immediately switch off the product. Remove the battery and keep it under observation. Allow it to cool down. Contact Hilti service.
The product is overloaded (application limit exceeded).
  • Select a product that is suitable for the intended purpose.
No response from the LEDs on the battery.
The battery is not fully inserted.
  • Push the battery in until it engages with a double click.
The battery is discharged.
  • Change the battery and charge the empty battery.
The battery is too hot or too cold.
  • Bring the battery to the recommended working temperature.
1 LED on the battery flashes.
The battery is discharged.
  • Change the battery and charge the empty battery.
The battery is too hot or too cold.
  • Bring the battery to the recommended working temperature.
4 LEDs on the battery flash.
Product momentarily overloaded.
  • Release the control switch and then press it again.
Protection against overheating.
  • Allow the product to cool down and clean the air vents.
Product does not develop full power.
The control switch is not fully pressed.
  • Press the control switch as far as it will go.
The half-power button is engaged.
  • Press the "half-power" button.
Drill bit does not rotate.
The function selector switch is not engaged or is in the "Chiseling" position Image alternative or the "Chisel positioning" position Image alternative.
  • With the motor at a standstill, set the function selector switch to the "Hammer drilling" Image alternative position.
The insert tool cannot be released from the chuck.
The chuck is not pulled back fully.
  • Pull the chuck back as far as it will go and remove the accessory tool.
The side handle is not fitted correctly.
  • Disengage the side handle and refit it correctly so that the clamping band and side handle engage in the recess.
Product does not start.
The electronic restart interlock is activated after an interruption in the electric supply.
  • Switch the product off and then on again.
The service indicator lights.
Service limit time reached.
  • Have the product repaired by Hilti Service.
The service indicator blinks.
The product is faulty.
  • Have the product repaired by Hilti Service.
The ON/OFF indicator flashes.
Product momentarily overloaded.
  • Release the control switch and then press it again.
Protection against overheating.
  • Allow the product to cool down and clean the air vents.

Disposal

Image alternative Most of the materials from which Hilti tools and appliances are manufactured can be recycled. The materials must be correctly separated before they can be recycled. In many countries, your old tools, machines or appliances can be returned to Hilti for recycling. Ask Hilti Service or your Hilti representative for further information.
Image alternative
  • Do not dispose of power tools, electronic equipment or batteries as household waste!

Manufacturer’s warranty

  • Please contact your local Hilti representative if you have questions about the warranty conditions.