Irwin Tools 326 Series Rotary hammer masonry percussion drill bit perfectly fits all hammer drills with 3-Jaw or Jacobs chuck. Shot-peened and double-tempered bit features 50-53 HrC chrome vanadium spring steel and copper braze tip. Hot isostatically pressed bit provides increased life and breakage resistance. It has a dimension of 1/4-Inch Dia x 4-Inch. This bit has straight shank of size 1/4-Inch. It features two twist, double grounded type flute of length 2-inches. An unique flute geometry aids to remove dust from the hole quickly and easily. The copper braze material offers high heat resistance while optimizing tip loss. Drill bit meets ANSI standards.