Irwin 49911 I-100 SERIES SOLID CENTER AUGER DRILL BIT, CLEAN CUTTING SPUR 11/16" X 7.5"

Solid center design provides extra rigidity while boring. Wide lands keep the bit straight as it bores through the hole. The flutes are ground behind the lands to funnel chips to the inside of the bit and away from the outside diameter, producing a faster, cleaner cut. Single-spur cutting edge scribes the circumference of the hole for a smoother finish. Coarse screw point provides fast boring in hard and soft woods. All bits have a 4-1/2" twist length and a 7-1/2" overall length. Full-length heat treated bit guards against bending in heavy-duty applications and strengthens the twist where the greatest strain occurs. Shank size: 5/16".