Features: 1. 100% brand new and high quality. 2. The shank is forged with high speed steel, which is sturdy and not easy to deform. 3. Made of high quality carbide material, the drill bit tip is of high hardness and hard to break. 4. Sharp sawtooth makes sure fast and smooth cut under high speed. 5. Can be installed on electric rotary tool to remove welding spot. Specification: Material: High Speed Steel + Carbide Color: Silver + Black Total Length: 77mm / 3.03in Shank Diameter: Sawtooth Circle Diameter: 3/8"(9.5mm), 5/16"(8mm) Weight: Approx. 23-48g Package Includes: 1x 5/16" drill bit or 1 x 3/8" drill bit 1x 5/16" drill bit (Based on your choice)