Based on our award-winning Nail Chipper auger bits, the Duo’s offer a double cut design to chip away at nails in studs and other framework, leaving a cleaner hole for conduit and wiring. Safer to use when encountering fasteners by nearly eliminating kick-back encountered with traditional ship augers. Lightweight design extends tool and battery life. Easily resharpened. 7/16” quick-change shank. 18″ OAL. 1″ DIA.