Blue-Groove point and cutting edge for faster chip removal - 4x faster than standard spade bits. 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. Fits all standard quick change chucks. 6-piece pouched set includes bit sizes 3/8", 1/2", 5/8", 3/4", 7/8", and 1".