SDS–max® bit system tool–free bit changes with automatic bit locking, dust protection and maximum impact energy transfer rate. Combination dual mode selector 2 modes of operation, rotary hammer and hammer only mode. Variable–speed dial for accurate bit starting and controlled chipping applications. Constant Response circuitry provides soft–start, maintains constant speed under load, provides overload protection. Service Minder light indicates when preventative maintenance is required. Vario–Lock positioning rotates and locks chisel into 12 different positions to optimize working angle. Padded rear handle absorbs shock for operator comfort. Integral clutch helps minimize torque reaction. 360° Auxiliary handle provides a wide range of movement along with operator comfort. Double insulated, UL listed, complies to OSHA.