Add to Favorite Sellers. 121579C1 12-volt (3 Terminal) Voltage Regulator Fits International Tractor. Quality Aftermarket 121579C1 12-volt (3 Terminal) Voltage Regulator Fits International Tractor Fits: 404, 424, 504, 606, 656, 706, 806; Industrials Specifications For use on tractors w/ generators. See website for all applications. We recommend verifying the proper fit for your application with a parts catalog or other reference documents. All aftermarket items have been hand selected by our team and are continuously monitored by a quality control department. Should a craftsmanship or fitment concern be identified, JJAgParts will be sure to work with our customers to stand behind our products. Be sure to check out our other listings for great aftermarket and NOS items! Don’t forget to leave us feedback and we will be sure to do the same! . Thank you for this opportunity to earn your business! Thank you for looking! We appreciate the opportunity to earn your business. Feel free to ask any questions you may have.