21/32" X 3/16" HSS Aircraft Counterbore 1/4" Shank Quantity:1 Part Number: Assortment Kit #257

Part Number: Assortment Kit #257

Part Number DWDRSD1-5/32

Part Number DWDBL47/64

they perform reliably in a range of materials

21/32" X 3/16" HSS Aircraft Counterbore 1/4" Shank Quantity:1 Part Number: Assortment Kit #257Product 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