Extend your reach by 18 inch when drilling with Milwaukee selfeed bits, auger bits and hole saws. Accepts all 7/16 inch hex, secures with a hex key included. The 7/16 inch hex fits both 3 jawed chucks, 1/2 inch drill capacity and larger, as well as 7/16 inch quick change chucks.Find the EXTENSION DRILBIT7/16X18 at Ace.