spiral grooves 25°, progressive tap, up to 1.5 x D, HSS-E_PM, metric ISO-thread, right thread, Tolerance field ISO2 / 6H, forme of taper lead C (2-3 x P), cylinder shank with square piece, number of teeth 2-4 Power class H For high-strength materials with a strength <900...1200 N/mm2, tempered steels, alloyed tool steels, hardened steels, some non-ferrous metals of special quality. Length of taper lead: 2.5 x P Hole Type: pocket holes < 1.5 x d. Designs: M2: H350-3, reinforced shaft, DIN 371, Teeth:2 M2.5...M10: H350-3, reinforced shaft, DIN 371, Teeth:3 M12...M30: H450-3, falling through shaft, DIN 376, Teeth:4