18 V x 2 Cordless rotary hammer. 8.0 Joules (EPTA) impact energy delivers high performance equivalent to HR4013C. Newly-developed BL motor delivers high power and excellent performance equivalent to corded model HR4013C. Active feedback sensing technology (AFT) turns the motor off if bit rotation is suddenly forced to stop. Auto-start wireless system (AWS) connects to compatible vacuum cleaners with Bluetooth.