Dash forward with irresistible force: Upgraded dry drilling diamond drill bits integrate wax lubricant, which melts and cools the cutting surface when dry drilling (water can be used as additional cooling to extend the life of the drill bit). Built-in surface plating prevents the drill bit from rusting, cutting faster and lasting longer Worry-free compatibility with major drill bits: Diamond drill bits are designed with a sturdy hexagonal shank, which is compatible with most machines, such as hand drills, angle grinders and bench drills, and can also be matched with side grooves to help remove debris and drill smoothly and quickly; depth markings are also useful for precise projects Universal: Diamond drill bit set is designed for handling materials such as stone, granite, marble, porcelain, ceramic and hard tile. The core tile drill bits are suitable for both industrial use in tough working conditions and for domestic use Easy to operate: To make the work easier, start drilling at a 45 degree angle and then gradually raise the drill bit to an upright position What you get: 5 pieces of 6mm diamond drill bits, a decent packaging, 5 individual boxes and friendly customer service