IDEAL Nailbiter 7/8-in Woodboring Ship Auger Drill BitNailbiter premium dual helix construction Twin cutting edges for fast and smooth drilling, even through nail embedded lumber Dual induction heat treated ensures durability staying sharper longer Heavy duty lead screw designed for quick gripping and penetration power 7 16 in. x 7. 5 in. hex shank Quick change shank design Full black oxide coating prevents rust Features Series Name Nailbiter Sub Brand N A Bit Type Ship auger bit Bit Length 7 1 2 in