Rubi 50mm Dry Cutting Diamond Drill Bit (04914)50mm DRYGRES Drill bit The DRYGRES range of diamond drill bits are recommended for the drilling of all types of ceramic tiles, especially porcelain tiles, and other covering materials such as marble and granite. In the DRYGRES range of drill bits, RUBI has used VACUUM BRAZED technology, which increases resistance to temperature and friction, to fix the diamond particles in the cutting area. DRYGRES diamond drill bits are made for dry cutting and can