1-1/8" X 5/16" Pilot Hole HSS Taper Shank Counterbore Quantity:1 STI Tap: 1/2"-20 STI

STI Tap: 1/2"-20 STI

These counterbores are made of two-piece construction

Part Number: Assortment Kit #145378 Pieces - Fine Thread

Part Number: BIT-D/ACO3/8X31/64

Part Number SDS4F3812

1-1/8" X 5/16" Pilot Hole HSS Taper Shank Counterbore Quantity:1 STI Tap: 1/2"-20 STIProduct 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