Heller hss co cobalt twist drills din 338 rn heller 21273 1 these 32mm hss co cobalt twist drills from heller are equipped to tackle the toughest drilling jobs in stainless steel and metal they are made from a special hss steel with a 5 cobalt content sold in packs of 10 heller 21273 1 0990 hss co cobalt twist drills din 338 rn 32mm pack of 10