4BA Threaded Shank Counterbore • HSS • Used to enlarge the opening of a hole to allow room for the head of a fastener List Number MC27004 Substrate HSS Package Quantity 1 Shank 1/4 Length 2-1/2 Flute Count 2 Bolt 4BA Pilot Diameter 0.156 Pilot Length 7/32 Cut Length 7/16 Diameter 0.251 SKU: MC27004 Category: Counterbores Related products LGS14-3 Weldon Tu-Lip Conterbore Item #: CW90343 LGS12-3 Weldon Tu-Lip Conterbore Item #: CW90323 LGS8-2 Weldon Tu-Lip Conterbore Item #: CW90282