HSS cylindrical metal drill bit 8 x 117 mm (x 1) for drilling copper, brass, zinc, plastic, etc. Plus points: no more drill bits jamming in tools, less friction, improved service life and excellent malleability. · · · Cylindrical shank. · · Monoblock head. · · Helix angle between 23° and 33°. · · For drilling copper, brass, nickel, zinc and plastics. · · Particularly suitable for 600 N/mm² carbon steels, standard 800 N/mm² steels and standard 900 N/mm² steel alloys. · · Not suitable for drilling in stainless steel.