DEWALT Powerstack 20-volt Max Variable Speed Brushless 1/2-in square Drive Cordless Impact Wrench (Battery Included) in the Impact Wrenches department at Lowes.com
DEWALT 20V MAX XR Impact Wrench, Cordless, 1/2-Inch with Detent Pin Anvil, 330-lbs of Torque, 3,100 IPM, Bare Tool Only (DCF894B) - Amazon.com
DEWALT ATOMIC 20V MAX 5/8" Brushless SDS PLUS Rotary Hammer Bare Tool DCH172B from DEWALT - Acme Tools