18 Volt Compact tough drill driver with (2) 1.5 Ah batteries Four-pole high-performance motor for maximum power in the most compact size New patented gear train and clutch enables most compact design in its class and lightest weight Flexible power system-both DD and HDD are compatible with every 18-volt lithium-ion Bosch battery Ergonomic grip zone-small diameter enables better gripping and greater comfort Modified orientation relative to handle increases comfort