Threading gauges, pictured on the right, are also referred to as pitch gauges and are used to measure the pitch or lead of screw threads. The uppermost gauge in the image is an ISO metric pitch gauge, the larger gauge in the center is for measuring the Acme Thread Form, and the lower gauge is for imperial screws.
Thread pitch gauges are used as a reference tool in determining the pitch of a thread that is on a screw or in a tapped hole. This tool is not used as a precision measuring instrument. This device allows the user to determine the profile of the given thread and quickly categorize the thread by shape and pitch. This device also saves time, in that it removes the need for the user to measure and calculate the thread pitch of the threaded item.
