Rotary Vise for Optical Comparators This rotary vise model mounts directly to an optical comparator stage. It has spring-loaded keys for most brands of comparators, or a set of t-nuts for Mitutoyo brand comparators since they have a different dovetail slot that will work with t-nuts. Features include... 1.25" Wide Vise 2.9" Clamping Range 360?ø Rotation in 1?ø Increments Steel Construction with Precision Ground Finish