Special featuresDRYGRES PREMIUM diamond drill bits are the most economical solution for users who need to dry drill holes of different diameters in all types of tiles.The DRYGRES PREMIUM range of diamond drill bits is recommended for drilling all types of ceramic tiles, especially porcelain tiles, and other wall or floor tiles such as marble and granite.In the DRYGRES PREMIUM series, RUBI has used VACUUM BRAZED vacuum brazing technology, which increases resistance to high temperatures and friction by securing the diamond particles in the drilling section.The DRYGRES PREMIUM diamond drill bit kit is primarily designed to give the tiler the best results when drilling various holes for water pipes, drainage, electrical connections, etc.The DRYGRES PREMIUM kits consist of: - MULTIDRILL guide - 28, 35, 43 and 68 mm diamond drill bits (ref. 51931) - 28, 35, 43, 50 and 68 mm diamond drill bits (ref. 51937) - 6, 8, 20, 35, 50 and 68 mm diamond drill bits (ref. 51929) - CaseDRYGRES PREMIUM diamond drill bits are designed for dry drilling and, thanks to their M14 threaded connection, can be used directly on an angle grinder or on a drill, using the drill adapter (ref. 05976). The average lifespan of DRYGRES PREMIUM diamond drill bits Ø 20 to 85 mm is 150 holes. The average lifespan of the drill bits ALWAYS depends on the type of material, its thickness, proper cooling, and correct use.The drilling depth of DRYGRES PREMIUM diamond drill bits is 30 mm for diameters from Ø 6 to 35 mm and 38 mm for diameters from Ø 43 to 85 mm.DRYGRES PREMIUM diamond drill bits (diameters Ø 20 to 85 mm) have a side opening that improves the cooling of the drill bit and makes it easier to remove drilling debris after each drilling. Before reusing the drill bit, all debris must be removed from the drill head. The models with Ø 43 to 85 mm diameter are segmented to provide greater stability during drilling.The maximum speed for using DRYGRES PREMIUM diamond drill bits is 14,000 rpm.For a better finish and longer drill bit life, it is important to maintain the recommended rotation speed and to make a pendulum motion with the drill bit during drilling.