Genuine Ariens Snowblower Auger Gear set for Older models with cast iron gear cases. This set has the standard # 10183 Helicon Gear for 1 Diameter Shaft. The worm shaft is 12-5/8 long. We have a few Helicon Gears left the are of the 7/8 diameter shaft version. We have 4 different versions of Worm Shafts. Please check your old parts for proper application. Please specify which size gear and shaft you need. All of these gear sets are NOS UNUSED Ariens parts from an old inventory. There may be signs of oxidation from age. This will not affect the use. This list is for one (1) gear set. One Helicon Gear and One Worm Shaft.