Unified Fine thread plug gauge UNF0-80 1-72 2-64 4-48 6-40 8-36 10-32 12-28 Unified Coarse Thread gage UNC 1/4-20 5/16-18 3/8-16

Unified Fine thread plug gauge UNF0-80 1-72 2-64 4-48 6-40 8-36 10-32 12-28 Unified Coarse Thread gage UNC 1/4-20 5/16-18 3/8-16

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