Each diamond drill bit features a built-in wax lubricant that melts during use to cool the drill tip, help prevent diamond loss, and extend the life of the bit. Allow the bit to cool after each hole to maintain optimal performance.The package includes: 2 pcs 3/16 inch (5mm), 2 pcs 1/4 inch (6mm), 2 pcs 5/16 inch (8mm), 2 pcs 3/8 inch (10mm), and 2 pcs 1/2 inch (12mm) drill bits. This 10-piece set offers a variety of sizes for long-term use and replacement.The round shank is compatible with most common electric drills, angle grinders, and bench drills. The side groove design allows for faster debris removal, and depth markings on the bit enable precise drilling control.These dry diamond core drill bits use vacuum brazed diamond technology to drill clean, accurate holes in tile, ceramic, porcelain, glass, marble, stone, and masonry. Not suitable for wood.Product Name: Diamond Drill Bits Set Color: Black Material: Diamond Sizes: 3/16 inch (5mm), 1/4 inch (6mm), 5/16 inch (8mm), 3/8 inch (10mm), 1/2 inch (12mm) Package Contents: 1 set of diamond drill bits Note: Light reflection and display differences may cause slight variations between the color shown and the actual product. Measurement may vary by +/- 1-3 cm.