5/16" x 12" Drill Bit Premium PercussionThe DeWalt 5/16" x 12" drill bit premium percussion is an extremely durable and useful attachment. Use this to increase your efficiency and decrease your work time. Superior build quality means you will be using this bit for years with minimal wear and tear. A must have for any professional or do-it-yourselfer. Features: ROCK CARBIDE tip maximizes carbide surface contact for longer bit life Four flute design cleans debris out for fast, efficient drilling Three flats on shank eliminate bit slipping in chuck (except DW5232, DW5233, DW5237, DW5238)Specifications: Diameter: 5/16"Usable Length: 7"Overall Length: 12"DEWALT is firmly committed to being the best in the business, and this commitment to being number one extends to everything they do, from product design and engineering to manufacturing and service.