HSS material is stronger and more durable. -UNC：0#-80 TPI 2#-56 TPI 4#-40 TPI 6#-32 TPI 8#-32 TPI 10#-24 TPI 1/4-20 TPI 5/16-18 TPI 3/8-16 TPI 1/2-13 TPI. -Type: Hand Tap. -Sharp head, special sharpening technology, low cutting resistance, high hardness, and sharper opening.
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