This Self-Feed Bits for Drill provides clear cutting without effort. Self-Feed Bits for Drill Cuts Faster & Has Improved Balance with Reduced Runout. Shanks Have Flat Surfaces for Secure Chuck Grip. Feed Screws Removable & Replaceable. Feed Screw Provides Fast, Effortless Feeding Even in Gummy Wood. Double Sided Feed. Screw & Allen Wrench furnished With Each Bit - After Bit is Worn, You Can Reverse the Bit to the Other Side. Universal 7/16” shank.