Replacement castle nut for several Comer Gearboxes, used to mount blade carrier to gearbox. Comer has used two common castle nut sizes, this one measures M24X2.0 pitch, the other is a M30 and it can be found listed in our other store items. The nut will not fit the shafts requiring a M30 nut. We sell many replacement parts for the most manufacturers rotary cutters. If you don't see the parts you need listed please contact us we would love to earn your business. We are listing new items frequently so please check our store often. Part Numbers: 8.2.2.00515 We stock a wide variety of replacement parts for Agricultural Equipment please contact us if you have any questions or if you would like more information.