Bits are 3 fluted and Made from high speed stee Bits are 3 flute, Integral (fixed) pilot for cutting accuracy. Made from high speed steel. Have a 1/4x28 threaded shank. 4 Pc set of 100 degree countersink cutters. Has standard 1/4-28 thread 4 pc set of 100° countersink bits, 1/2 diameter., #40, #30, #21, #12., Bits are 3 flute, Integral (fixed) pilot for cutting accuracy. ROSEBUD DEBURR / COUNTERSINK 100 DEGREE – Aircraft Engineers Store | UK Drill Bit Set Dargan Tools Countersink Bit Set 3pce - Tool Source High Speed Steel Countersink Bits Includes #40, #30, #21, #12 bit sizes, 1/2 diameter 3PC COUNTERSINK SET - Almandoz Hardware Ltd 4 Pc set of 100 degree countersink cutters. Made from high speed steel.
