Dry Diamond Drill Bits Set, 5 Pcs., Round Shank 1/4, 5/16, 3/8, 1/2 Inch, With Product Details When renovating your kitchen or bathroom wallsor fastening mirrors in bathroom or installing shower, you will need to drillholes on mirrors or tiles without cracking them, hence you will need to usethese diamond drill bits to make those holes very precise Our porcelain diamond core drill bit uses vacuum brazed technology, so the bit can be usedat a higher temperature cutting harder materials, great for drilling clean holes to granite, ceramic, glass stone brick andmarble tile stone Jars and similar materials (not for wood) Dry diamond drill bit integrates wax lubricant inside of the bit. During drilling,this integrated lubricant will melt to cool the cutting surface, perfectfor project which lubricant is not applicable. If additional cooling isrequired, water can be used to prolong the life of the bit and to remove thedebris during the drilling process. Steps to drill clean and precise holes: 1. Start Drilling the hole in anangle about 45 degrees to the surface, so the drill has the chance to start andwill prevent the drill slipping 2. Slowly move the drill bit intoa more up-right position and wobble the drill bit in the circular motion 3. Do not need to apply much pressure,let the drill bit do the work, you will feel the drill bit break through theback of the glass or tile once the hole is completed 4. Take care when using them as abit can glaze and burn out if use too fast Package includes: 2 x Bits diameter of 1/4 inch(6mm), 1 x Bit diameter of 5/16inch (8mm) 1 x Bit diameter of 3/8inch (10mm), 1 x Bit diameter of 1/2inch (12mm) 1 x Storage case Add Versatility to Your Tool: 5 Pieces of Dry Diamond Core Drill Bits Kit for drilling holes diameter of 1/4 inch(6mm), 5/16inch (8mm), 3/8inch (10mm) and 1/2inch (12mm); Vacuum Brazed Diamond Technology: Great for drilling clean holes to hard materials especially tiles, porcelain ground, granite ceramic glass mirror marble stone masonry brick (not for wood) Dry Drilling Design: Diamond Drill Bit integrated with wax lubricant inside which melts while dry drilling and cools the cutting surface; Water can be used as additional cooling to prolong the life of the bit Unique Details: Diamond coating enhances the drilling speed; Round Shank compatible with most machines such as Hand Drill, Angle Grinder, Bench Drill; Side flutes help to remove debris and drill holes smooth and fast; Depth mark useful for precise project Worry Free: This Diamond Drill Bits set comes with a portable storage case for convenient use and store. If you encounter any problems in using the products, please feel free to contact us for satisfactory customer service Payment We accept PayPal and credit cards via PayPal. Taxes - US We collect sales tax, as required by law. Shipping We make every effort of shipping within 3 business day of payment clearing. The estimated delivery time is 2 - 5 business days from the shipping date. Policies If you do need to return your item, please contact us via email (you will receive an email when your product ships with additional details - Subject: Important information about your purchase). You will then be provided with a return shipping label and packing slip. Pack the item carefully. Include the packing slip, apply the shipping label, and return the item within 30 business days of the date you request a return, or your return will be canceled. Once we receive your order we will inspect the return. Please allow up to 5 business days of receiving the returned item for your refund.