4Pcs Dry Diamond Core Drill Bits Set for Porcelain Tile Ceramic Marble Brick M14 Thread Hole Saw Mixed 25/35/50/68Mm. Artificial diamond and Steel body. 17.8 x 12.2 x 9.7 cm; 910 Grams. Porcelain tile, granite, marble, brick. Set 12=25mm, 35mm, 50mm, 68mm, each size 1pc. Multi-purpose drilling for ceramic tile, porcelain tile, granite, marble.. Special Designed with Hole in both Sides of Drill Bit for fast Removing Stone Chips and Improve drilling efficiency. Dry drilling without water, Use water for longer time. Lf you want to use electric drill or other machines, you can use SDS or Hex Shank Adapter. Recommended speed 6000RPM, maximum speed 11000RPM. We offer the best prices around on high quality products. Our E-store includes media such as books, movies, music and games while offering electronics, toys, sporting apparel, clothing, tools, general home, garden items and more. We upload new items Daily so be sure to visit us regularly for more items. We are always working hard to ensure your package arrives as soon as possible. We do not accept P. Please provide a physical address. We try our very best to make sure every customer is completely satisfied. If there’s a problem, message us! We’re happy to help.