Adjustable inside diameter pin gages are used to check straight bores, grooves, spherical radii, and spline and gear pitch diameters. A variety of interchangeable threaded contacts allows the gage to be altered to suit the application. The gage utilizes the principle and portability of an inside diameter micrometer with the accuracy, speed, and total retraction of the dial indicator range. The displays can be balanced, continuous dial, or digital indicators.