The deep, open-throat design of the Ship Auger bit clears chips for faster, cleaner cuts. The shank is 7/16'' hex to fit 1/2'' (13 mm) and larger three-jaw chucks. Used for heavy construction and repair work in mines, on docks and bridges as well as electrical work.PRODUCT FEATURES:- Bits drill through nails, wood, vinyl, plastics, and heavy timber. - Special bit steel with machine-ground flutes and polished edges for smooth, wobble-free boring. - Deep, open throat design clears chips for faster, cleaner cuts. - Feed-screw pilot draws bit into wood. - Full length is heat-treated and tempered. - Shanks are 7/16'' hex to fit 1/2'' (13 mm) and larger three-jaw chucks. - Head and twist are ground to correct clearance for easy removal from hole. - For heavy construction and repair work in mines, on docks and bridges, and for electrical work.