DEWALT DW5831-SDS Max Bit For Rotary Hammer, 4 Cutter, 2-Inch X 22-1/2-InchSDS Max High Impact Carbide 4 Cutter Drill Bits are manufactured with IRON BLAST TECHNOLOGY, a process that strengthens the bit to resist fatigue and results in extreme durability. The redesigned, 4 cutter carbide head offers 2X longer life and even stands up to rebar strikes. If you have our bits, we have your back. Includes 1X DEWALT Sds Max Bit For Rotary Hammer, 4 Cutter, 2 Inch X 22 1 2 Inch Features Extreme durability: IRON BLAST