Corded drills, screwdrivers -Spear head drill Highlights generic brand Spear head drill Description: 7-piece glass triangular drills, sharp edges, easy drilling High quality materials, strong and wear-resistant, easy to use, widely applicable Four-blade cutter head design, quenching and forging, effective drilling efficiency and stronger impact resistance Non-slip hexagonal shank design, shank diameter is 1/4 (6.35mm) , the electric drill is tighter Often used to drill glass, tile, porcelain, ceramics and other hard and fragile materials. Specification: Material: Steel Size Chart: Length: 74-94mm/2.91-3.70in Hole Diameter: 3-12mm/0.12-0.47in Package Include: 7pcs Drill Bits Note: 1. Please allow slight error due to manual measurement. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3. Wish you have a wonderful online shopping!