Abstract: The present invention is directed to an improved, multi purpose measuring device for determining various parameters of an externally threaded member. In particular, the invention includes a substantially ring shaped housing slidably supporting at least one pair of gage plugs having measuring assemblies mounted thereon. As the gage plugs are selectively moved through the housing to bring the measuring assemblies into contact with an externally threaded member for determining various parameters such as the actual and functional pitch diameters, the minor diameter and the concentricity of the threaded member.

Abstract: An improved measuring device for determining both major and pitch diameters of screw threads, gears, splines and the like, wherein attractable magnetic members attached to a movable spindle and fixed anvil serve to attract and retain gauging wires in their proper positions. An adjustable screw and spring assembly biases the spindle toward the anvil with a predetermined and readily adjustable pressure.