2-1/4" X 1/2" Pilot Hole HSS Taper Shank Counterbore Quantity:1 Part Number: Assortment Kit #182375

Part Number: Assortment Kit #182375 Pieces - M6 & M8 Coarse

Part Number: M20C120ASB12BO

Size 5/16"-20

Size m22 x 0

Internal Diameter: 7/16"-14

2-1/4" X 1/2" Pilot Hole HSS Taper Shank Counterbore Quantity:1 Part Number: Assortment Kit #182375Product 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