straight grooves, progressive tap, HSS-E, metric ISO-thread, right thread, Tolerance field ISO2 / 6H, forme of taper lead B (3.5-5.5 x P), cylinder shank with square piece Power class For high-strength steels. Length of taper lead 4 x P Hole Type: through holes. Designs: M2...M10: , reinforced shaft, DIN 371 M12...M24: , falling through shaft, DIN 376