6 PCS, 3/8″, Black and Gold Twist Drill Bits 3/8 in

6 PCS, 3/8″, Black and Gold Twist Drill Bits. Cobalt drill bits: Classic M2 High Speed Steel construction with Black and Gold finish for proven capability and durability. Hardness: M2 Twist drill bits’ Rock wall Hardness Level HRC 62-63.