"IRWIN INDUSTRIAL" SPADE DRILL BIT Cutting Diam :1/2"Overall Length : 6"SpeedborSpade Drill BitBlue-Groove point and cutting edge for faster chip removal - 4x faster than standard spade bitsDouble cutting spurs scribe the outside of the hole reducing breakout10% larger shank for added durabilityGrooved hex shank prevents slipping in drill chuck or bit extensionFits all standard quick change chucks