One New Aftermarket Replacement Fits Case - Fits International 4-Button Trans Disc (Spring Loaded, Rockford Design) For Tractor Models: 430 (Diesel 8297801-8650135), 440, 470 (8656925>), 480, 530 (Draft-O-Matic), 540 Series, 570, 634, 640. For Industrial/Construction Models: 480B (Diesel), 480C, 480Ck (Diesel), 580 (Diesel), 580B (Diesel), 580C, 580Ck (Diesel) Spline Diameter: 1.375" Spline Count: 21 Replaces Part Numbers: 1997844C1, A51840, A51840-R4B, 5403B- All OEM part numbers and logos are to be used for identification purposes only