Counterbore - HSS Straight Shank - Various Sizes

Counterbore High speed steel straight shank Used for drilling recessed holes into scales for Corby Bolts, Gulso Bolts, screws etc. Counterbore pilots must be purchased separately.  Uses a 1.5mm allen wrench or T6 torx drive(included).    Selection Guide: Corby bolts- 3/16" uses Counterbore #CB1 with Pilot #PIL1 1/4" uses Counterbore #CB2 with Pilot #PIL2 5/16" uses Counterbore #CB3 with Pilot #PIL3   Gulso Bolts- 1/4" uses Counterbore #CB2 with Pilot #PIL5 5/16" uses Counterbore #CB3 with Pilot #PIL2 3/8" uses Counterbore #CB4 with Pilot #PIL4