Nail Eater® Extreme 1/2" (12.7 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