Speedbor Ship Auger Bits with WeldTec - Speedbor with WeldTec Ship Auger Bits are made stronger and last longer because a harder cutting edge is welded to the base material. 2x nail cutting life compared to standard Irwin ship augers. Patent pending welded cutting edge. Aggressive screw pitch. Wide flutes. 7/16" quick change impact shank. Fully forged body on bits 3/4" diameter and larger.