【High quality material】 Made of high speed carbon steel with nickel plating which is durable and has a long life, ensures excellent for making a clean and precise hole. 【10 pieces include】 6mm、8mm、10mm、12mm、14mm、16mm、18mm、20mm、22mm、30mm 【Function】 Stable drilling at fast speed. Drill safely without damaging the border. Creates a precise, smooth cut without broken edges. 【Easy to Use】 Simple to use and convenient to use. Water is necessary for lubrication when drilling, make sure the cutter is kept cool to avoid damage and extend the life of the drill bit 【Widely used】 Perfect for glass of drilling, tile bottles, block jars, fiberglass porcelain tile ceramic, Mable slate, granite light stone. Ideal for home, hobbies, crafts, construction, etc. Feature: 1. Excellent for making clean, precise holes on glass and tiles 2. Works best with an electric drill (not included) 3. These diamond drill bits are capable of drilling into extremely hard materials such as stone and glass. Use a low speed setting and proper cooling, such as water lubrication. 4. Superior performance cut holes in marble, slate, glass, tile, stone, etc. 5. Using water as a coolant/lubricant will greatly extend the life of these hole saws. 6. Very easy to use, high quality, good performance, long life. Specifications: Color: Silver Material: nickel plated Use note: 1. Start your hole diagonally, make a round trace, then hold the drill straight. 2. Always use lubrication (water), otherwise the diamond core drill will burn. Package included: Hole saw set of diamond tool drill bit 10 pieces Delivered quantity: 10 pieces Product color: silver Product size: 6 mm, 8 mm, 10 mm , 12mm, 14mm, 16mm, 18mm, 20mm, 22mm, 30mm. Note: Manual measurement, please allow 1-3cm error.