Features & Details Efficient & Smooth Cutting: The glass drill bit is made of premium grade diamond, delivers more effective performance than a traditional carbide or bi-metal hole saw. Vacuum brazing technology makes it highly thermostable and durable to use. Complete Tool Set: Our porcelain drill bit includes 5 sizes:4/5", 1-3/8", 1-1/2", 2", 2-3/5". It features a 5-inch saw blade. Having these types available will help you cover almost all of your applications. The drill set also comes with a storage case for your convenient carrying. Humanized Structure: This hole saw drill bit set adopts 5/8"-11 universal thread, suits for angle grinder. The design of U-shaped chip grooves provides longer working life, fast and smooth drilling. Simple Operation: The diamond hole saw drill bit set can be used both dry and wet, to meet your various needs, recommended adding some water to prolong the service life. Wide Application: The diamond drill bit set ensures a clean and accurate hole on porcelain tile, granite, marble, and stone. It also applies to masonry, brick, and all similar materials.