Abstract: A dial indicator is supported by a device which relies on a differential screw to enable the feeler of the dial indicator to be precisely adjusted in very fine increments. In one embodiment, the differential screw extends between the two legs of a U-shaped element, the dial indicator being carried by one of the legs and being adjusted when the screw is turned to pivot the legs toward or away from one another. In another embodiment, the screw extends between two end-to-end links and is operable when turned to effect relative pivoting of the links.