5/16" X 3/32" Pilot Hole HSS Straight Shank Counterbore - High Performance & Durable Cutting Tool | Drill America Welding PPE Size: 1/2"-10

Size: 1/2"-10

Optimal for High-Amp Applications: Withstands higher amperages

Size: 2-5/16"

Size: 3-1/2"-8

5/16" X 3/32" Pilot Hole HSS Straight Shank Counterbore - High Performance & Durable Cutting Tool | Drill America Welding PPE Size: 1/2"-10Counterboring 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 counterbore cutter, and a