Nail Eater Extreme 1" (25.4 mm) hole diameter. 18" (457.2 mm)overall length. Improved cutting edge provides 30 percent longer life span. Patented new design for improved cutting and cleaner holes. Self-feeding screw point draws bit through wood. Unique patented design cutting angle - smoother starts, reduced cutting loads. Made of super tough, heat-treated steel. Cuts through nails and provides longer life. Shorty bits - for working in tight places, yet still can go through three abutting 2 x 4s.