Thread Check Inc. offers a complete line of Vermont Class ZZ plain pin gage sets certified to ISO 9002 and traceable to NIST. Class ZZ plain replacement pin gages are economically priced and readily available. Replace missing, damaged, or worn out gages from existing sets and libraries. Vermont class ZZ Black Guard class ZZ plain pin gages are specially treated with black oxide coating which penetrates the pin gage .000040 ‐ .000060 deep and acts as a visible wear indicator. The Black Guard also prevents rust and corrosion which extends the useful life of the gage. Class ZZ plain replacement pin gages provide quick and accurate measurements of hole sizes. Class ZZ replacement pin gages can be used to calculate distances between holes. These pin gages can be used to gage slot widths and check locations. They can be used to set snap gages and size in micrometers. Class ZZ pin gages are ideal to use for fixed limit go/no go gaging. Class ZZ plain replacement pin gages are offered in a wide range from .006 ‐ 1.0005 and in metric from .20mm to 25.49mm. They are available in plus and minus tolerances of .0002 or .005mm. All class ZZ pin gages are 2.0 in length and made of 52100 tool steel. They have a 10 micro inch surface finish and are round within .0001.All class ZZ pin gages over .060 are marked with size and direction of tolerance. Class ZZ plain pin gages are a must for anyone making frequent and varied measurements.