Blue-Groove point and cutting edge for faster chip removal. Double cutting spurs scribe the outside of the hole reducing breakout. 10% larger shank for added durability. Grooved hex shank prevents slipping in drill chuck or bit extension. Bit identification is simple with easy-to-read size markings. Standard length. Includes sizes: 3/8′, 1/2′, 5/8′, 3/4′, 7/8′, and 1′.