Selecting a Pin Gage on Amazon.com
A pin gauge, or pin gage, is a cylindrical plug for measuring the diameter of machined holes and slots. Also known as plug gauges or gage pins, they are a type of go/no-go gauge used to determine whether hole sizes are within tolerance. Pin gauges are manufactured to Class XX, X, Y, Z, and ZZ tolerance standards, with Class XX having the tightest tolerance. They are available in inch or metric sizes. A pin gauge set contains gauges of various sizes to enable a wide range of measurements. Pin gauges are usually made of either hardened tool steel or tungsten carbide to resist wear and maintain tolerance. Some include a certificate of accuracy traceable to the National Institute of Standards and Technology (NIST). To aid go/no-go gauging, pin gauges may be placed in a pin gauge handle that has a green (go) end and a red (no-go) end. They are commonly used for quality control in machining, milling, and manufacturing applications.