Hercules 20V Brushless Cordless 3/8 in. Compact 3-Speed Impact Wrench – Tool Only - Delivers up to 525 ft. lbs. breakaway torque and 229 ft. lbs. of fastening torque - Amazon.com
Harbor Freight's Hercules 20V 1/2 in. Compact Impact Wrench Reviewed
20V Brushless Cordless, 3/8 in. Compact, 4-Mode Impact Wrench – Tool Only