Description: Wide applications: This kind of drill bit is suitable for ceramic, tile, glass, stone, wood, stainless steel, plastic and other materials, convenient for you to drill holes on the board, making your work easier. Compatibility: This drilling hole opener is suitable for hand electric drills, which can replace the old or damaged one perfectly, saving effort for you. Anti-abrasion: The tip of the hole opener is coated with hard alloy, sturdy and long-lasting, and the sharpened design works with low resistance when drilling, you can use it for a long time without being broken or damaged. Portable: You can store the drill sharpener in a tool case to carry when not in use, keeping your tools organized and saving space for your drawer, not easy to make trouble for you. Optional: There are designed with 7 kinds of sizes for choosing, including 3mm, 4mm, 5mm, 6mm, 8mm, 10mm and 12mm, enough to meet your different needs, you can pick the suitable type to order. Specification: Material: hard alloy. Color: black. Size: approx. 3mm/0.12inch, 4mm/0.16inch, 5mm/0.2inch, 6mm/0.24inch, 8mm/0.31inch, 10mm/0.39inch, 12mm/0.47inch. Size Chart: Due to the light and screen difference, the item's color may be slightly different from the pictures. Please allow a slight deviation for the measurement data and make sure you do not mind before ordering. Package Includes: Type 1: 4 Pieces Drill Bits. Type 2: 5 Pieces Drill Bits. Type 3: 7 Pieces Drill Bits.