The Driltec AE-305-136 5/8" x 4" (Usable Length) x 10" Spline Shank Bit with a Jet-Head® carbide head provides for both smooth and high performance drilling with less vibration. With the Jet-Head® tip you have less wear and tear on both the rotary hammer and the operator. This carbide bit also has a center point for easier start up. The large relief slots provide for efficient dust removal. The Driltec Jet-Head® Bits provide for exact round holes. Bit diameters meet ANSI standards.