Carbide-tipped with center point, 2 main cutting edges and 2 pre-cutters, perfect CNC diamond grinding, professional service life thanks to high-quality carbide tipping and special serrated edge (from ø 25 mm) on main cutting edges, ø 8-12 mm have a solid carbide head and a spiral, from ø 50 mm with hexagonal shank for better power transmission, clean, tear-free holes in all hardwoods, coated and KS-coated chipboard and many plastics such as acrylic Plexiglas, Corian®, GRP, HPL coating, polycarbonate, PVC and Trespa®, only recommended for stationary use, very low feed forces with professional tool life even in hard solid plastics and hardwoods, for freehand use we recommend HM-Bormax series 1663