"IRWIN" WELDTEC SHIP AUGER *1" x 17" *7/16" quick change impact shank *Full forged body on bits 3/4" diameter or larger*Speedbor with Weldtec ship auger bits are made stronger and last longer *Harder cutting edge is welded to the base material *2 times nail cutting life, compared to standard Irwin ship augers *Patent pending welded cutting edge *Aggressivescrew pitch *Wide flutes *Discovery ACC, NBR, SUP