Answer: callipers

AnswerCrossword Clue
callipersA metal support for a person's leg
callipersA motor-vehicle or bicycle brake consisting of two or more hinged components
callipersAn instrument performing a similar function but having one linear component sliding along another, with two parallel jaws and a vernier scale
callipersAn instrument for measuring external or internal dimensions, having two hinged legs resembling a pair of compasses and in-turned or out-turned points