Cordless 20V Series - Hammer Cordless 20V Series - Hammer Voltage 20 V Battery Availability 2.0 Ah / 3.0 Ah / 4.0 Ah Charge Time 1 h / 3 h No-load Speed 0 - 1700/3000rpm Impact Energy 2J Function 3 Working Capacity 30mm for wood Overheating Protection System Yes