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.  Safe Lock-on Button & Rotation Handle --- Push reverse/forward button to the middle position, to lock the trigger, prevent accidental press. 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.    Specifications:  Motor: Brushless Motor  Function: Electric Hammer, Electric Pick, Electric Drill  Type: 1x4.0Ah battery / 2x4.0Ah battery / 1x6.0Ah battery / 2x6.0Ah battery (optional)  Plug: US/EU/UK (optional)  Battert Capacity: 4000mAh / 6000mAh (optional)  No Load Speed: 0-980r/min  Hammer frequency: 0-6200p/min  Adjustable Speed: Stepless speed change  Input Voltage: AC 110V-240V  Charging Current: 2.0A  Power: 21V 900W  Input power frequency: 50-60HZ  Battery Voltage: DC 10-21V  Insulation Degree: Dual Insulation  Chuck: SDS Plus  Max. Drill Diameter: 26mm  Impact Driver: 2580g/91oz  Impact Driver Size: 33.5*20.5cm/13.2*8.1in  Package Weight:      With One Battery Set: 5665g / 199.82oz      With Two Battery Set: 6374g / 224.83oz  Package Size: 43*33*12cm/16.9*13.0*4.7in    Package List:  1 * Multifunction Impact Driver  1 * Charger  1 * Battery  1 * Handle Bar  1 * Depth Measuring Scale  9 * Attachment  1 * Carry Box