Bosch DH507 12-Pound 10-Amp Variable Speed SDS-Max Demolition Hammer Ergonomic Grip Area: Maximum comfort when chiseling in tight spaces or in a wide variety of positions Hammer Mode/Vario-Lock Selector: Selector easily switches from hammer mode to the vario-lock feature Vario-Lock Positioning: Rotates and locks chisel into 12 different positions to optimize the working angle Lock-on Button: For extended use applications Variable Speed Trigger/Dial: For controlled chiseling applications