The premium version has a thinner wall thickness, therefore cuts faster and has a longer service life. Vacuum-brazed diamond for high speeds and longer tool life. The core bits are filled with kerosene, which ensures cooling and abrasive retention. With 14" E6.3 holder for use in all standard (cordless) machines. To be used at the highest possible speed, min. 1,500 rpm. Regular cooling breaks, possibly with water, increase the service life of the product. For drilling holes in hard fired tiles, natural stone, ceramic tiles and thin granite. In a set of 5 pcs. 5-12 mm