1" x 18", Nail Eater Bit, For Improved Cutting & Cleaner Holes, Self Feeding Screw Point Draws Bit Through Wood, Unique Patented Design Cutting Angle, Smoother Starts, Reduced Cutting Loads, Heat Treated Steel, Cuts Through Nails & Provides Longer Life, Shorty Bits, For Working In Tight Places, Overall Length 18", 457.2 mm, Twist Length 15", 381 mm.