Rotational Restraint in Anchoring-To-Concrete Module

I am designing a column base plate for a stand off condition with grout. There is an option to specify a "Rotational Restraint" Level as either 1 (fixture can freely rotate) or 2 (full restraint, fixture cannot rotate). I looked in the user manual and did not find any additional information as to which type of rotation this refers to or what the fixture represents. Clarification would be appreciated.