The OEMTOOLS? 20V MAX* Lithium-ion 3/8 In. Drive Cordless Impact Wrench is used for tightening or loosening nuts and bolts, automotive repair, body shop maintenance and other applications. The Impact Wrench uses a high-capacity, 1.5Ah Lithium-ion slide battery with the latest technology for longer life and more power to get the job done. The Impact Wrench has an electric brake that stops rotation of the tool immediately when the trigger is released to reduce work time for continuous jobs. This power tool is designed with a heavy duty, cast aluminum gear head for strength and durability and an ergonomic, rubber mold-over grip for added comfort. The battery resists self-discharge and will remain ready-to-use even after storage. The diagnostic, fast charger provides optimization with an auto shut-off feature to save energy, prevent over-charge and enhance battery life.