Thread measuring machines are built with a primary measuring body that holds and centers a threaded workpiece and a linear gauge connected with a cable to a digital display. These machines are used to measure major diameter, pitch, and minor diameters of external threads. They can be used with Inch, Metric, Whitworth, BSPT, or NPT straight threads and straight and tapered pipe threads. Thread measuring machine accessories include tools needed to measure the pitch diameter of externally threaded parts. Accessories also include clamps needed to secure larger workpieces with internal bores.