Irwin 324011 2 Cutter Hammer Drill Bit"IRWIN INDUSTRIAL" HAMMER DRILL BIT The Irwin Tools 324011 Masonry Drill Bit is a fast and durable bit for the professional user. The bit features a Chrome Vanadium Spring Steel shaft that is through hardened for Superior Durability. The Shot peened, double tempered finish reduces breakage. The Bit also features a tip with a Copper brazed material that gives high heat resistance and reduced tip loss. The Spline shank fits all Spline rotary hammers.