Features: Digital Brushless Motor --- Provides efficient, high-performance power when drilling through tough surfaces like brick, concrete, and other masonry. And no need replace carbon brush and with larger motor rotor stator, lower power consumption longevity and no burn-in phenomenon. 4-Mode Select --- This rotary hammer drill includes drill, hammer drill, chisel and chisel alignment settings 4 functions in 1 tool, money saving, time saving and increasing efficiency. Variable Speed --- High performance brushless motor with 0-6200p/min impact rated and 0-980r/min no-load variable speed and reverse function help to complete heavy duty projects. Lock-on Button Rotation Handle --- With lock button to enable you to lock the speed without a constant grip on the trigger to reduce fatigue. Anti-slip plastic and 360 degree adjustable detachable handle provides a comfortable grip and control feeling. Wide Application --- Professional rotary hammer drill delivering powerful impact and hammer strength to complete heavy duty projects on wood, masonry, solid steel and concrete which means that most of the work needs can be met. Large Batterry Capacity Depth Gauge --- 398TV 21V 4.0Ah Lithium battery using time can up to 180 min under no load rotation. With 19.5cm(7.7 inch) metal depth gauge lasts a longer service life, offering greater control, precision.