10 sizes (diameter): 6 mm (1/4'), 8 mm (5/16'), 10 mm (3/8'), 12 mm (1/2'), 15 mm (3/5'), 16mm (5/8''), 18mm (11/16''), 20mm (3/4''), 22mm (7/8''), 30mm (1-1/5''). Meets most of your needs. Stainless and Durable: Made of high-strength carbon steel with a smooth nickel-plated surface to extend the service life. Fast, Precise and Smooth Cutting: Coated with high-quality diamond to improve drilling speed and create a clean, high-precision, and smooth cut without broken edges in seconds. Application: Drilling glass, tile bottles, block jars, fiberglass porcelain tile, ceramic, marble slate, light granite stone. Do not use on concrete or at depths greater than about 1/2''. Caution: Please keep the speed at 800-1000 per minute, keep adding water to cool the drill, strictly prohibit dry drilling. Product Description 10Pcs Diamond Drill Bit Set Glass Hole Saw for Glass Tile Ceramic Marble Bottles DIY 6mm-30mm Features: Good Performance: Diamond dust coating provides superior cutting