DeWalt Hammer drill bit

4-Cutting Geometry - For clean, round drill holes and consistently high drilling speed. Almost eliminates the risk of the drill getting stuck in reinforced concrete. Solid Carbide Head - For extremely long life with optimal drilling performance even in reinforced concrete (from 16mm diameter). Extended Helix - For optimized transport of drill cuttings and faster drilling progress. 4-Fold Helix - Best possible drilling progress and extended lifespan of the drill head thanks to optimized removal of drill cuttings through four true drilling flutes. Core Reinforcement - For optimal impact energy transfer and break stability for maximum durability and reliability. Iron Blast Technology - By bombarding the surface with steel balls, stresses in the drill head are reduced and strength along the flute is increased (from 16mm diameter).