Fine grade high durable carbide long lifetime best wear resistance 2 flute u shape standard lifetime good dust removal 3 cutter vacuum brazing and hardening for fast breakthrough and good removal of large pieces long shank for breakthrough drilling suitable for breakthroughs with diameters from 45 mm to 80 mm in concrete masonry limestone eg for fixing cables and pipes outside one piece tool bell shaped head with asymmetrically positioned carbide pins and centre cutter large v