Ingersoll Rand W7150-K2 1/2-Inch High-Torque Impactool, Charger, 2 Li-ion Batteries and Case Kit Power - 1100 ft-lb nut-busting torque from a tool weighing just 6.8 lb  best power to weight ratio in its class Durability- High-efficiency rare earth magnet motor, high-capacity variable speed trigger, all-metal drive train, and metal-reinforced housing enable this tool to stand up to the toughest jobs Comfort - Optimized balance combined with an ergonomic handle and soft touch over-molded grip provide increased comfort in extended use Long life 20V lithium-ion battery delivers high-charge capacity and low internal impedance for maximum power delivery and run time. 	Intelligent battery management system (BMS) provides power-level and current control from the battery to the switch to the motor for optimum efficiency