1-1/8" X 5/16" Pilot Hole HSS Taper Shank Counterbore BoltsandNuts.com Size 1/4"-48

Size 1/4"-48

Tap Drill Size 1-3/32"

Metric Hex Nuts Zinc Plated

Part Number: DUR002-95

Part Number DWDST1-3/16

1-1/8" X 5/16" Pilot Hole HSS Taper Shank Counterbore BoltsandNuts.com Size 1/4"-48Product 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