Simpson Strong-Tie offers a complete line of premium-quality drill bits, core bits and chisels to handle any drilling and demolition need. SDS-max shank bits have a chisel-shaped drill bit head which penetrates the material and directs concrete dust into the multi-flute spiral. The proprietary flute geometry reduces vibration and optimizes impact energy transfers from the rotary hammer into the drill bit tip which enhances drilling speed and durability and reduces noise, stress and vibration on the operator. All the features of single-cutter bits are designed to improve durability and drilling speed. 9/16 in. x 21 in. SDS-max® Shank Drill Bit (Pack of 5).