Speedbor 1891777 Irwin Tools Blue-Groove Spade Bits, 5-Piece, Slim Case Blue-Groove point and cutting edge remove chips 4x faster than standard spade bits for cleaner holes and less binding Dual-cutting spurs scribe the outside of the hole reducing breakout. 10% larger shank for added durability Shorter bit length gets into confined spaces (between studs) where standard lengths will not fit Grooved hex shank is compatible with all 1/4-inch quick-change chucks, including impact drills and reduces slipping in standard chucks