The metabo hss g twist drill bit set is suitable for drilling steel and cast steel alloyed and unalloyed grey cast iron malleable cast iron ductile cast iron sintered iron nickel silver graphite non ferrous metals and plastic up to 900 nmm tensile strength the bits have been ground with a cylindrical din 338 type n 135 crosswise grinding tip they are supplied in a metal tin and it contains one of each size 1 15 2 25 3 35 4 45 5 55 6 65 7 75 8 85 9 95 10mm