17/32" X 1/8" HSS Aircraft Counterbore 1/4" Shank BoltsandNuts.com Tap: 5/16"-18

Tap: 5/16"-18

Part Number: BIT-KFDC

Number of Flutes 6

HSS Round Dies are for use in making new threads or re-threading existing threads

Part Number D/A3F21/32

17/32" X 1/8" HSS Aircraft Counterbore 1/4" Shank BoltsandNuts.com Tap: 5/16"-18Product Description Counterboring is the enlargement of a portion of a hole that has previously been formed. If the counterbored portion is shallow (1 8" or less), the operations is usually known as spot facing; for example, a flat seat for a bolt head or nut. If, on the other hand, the hole is enlarged to a considerable depth, it is designated as counterboring. These counterbores are made of two piece construction, having an integral shank and