One New Aftermarket Replacement Muffler Fits: Fits International Tractors: Hydro 70, Hydro 86, 666 (with C291 Gas), 686 (with C291 Gas), 706 (with C263 & C291 Gas), 766 (with C291 Gas), 806 (with C301 Gas/D361 Diesel), 826 (with C301 Gas), 856 (with C301 Gas/D407 Diesel) Technical Information: Inlet ID 2-15/16″, Outlet OD 3″, O/A Length 34″, Inlet Length 3-1/4″, Outlet Length 8-1/4″, Shell Length 23″ Replaces Part Numbers: 530578R4, 570578R3 Models This part fits: 666, 686, 706, 766, 806, 826, 856, H70, H86 Reference Numbers: 11650T, 530578R1, 530578R1-A, 530578R2, 530578R2-A, 530578R3, 530578R3-A, 530578R4, 530578R4-A, 530578R91, 530578R94, 570578R3, A-530578R4, A-530578R4-A, IH-27, PM11650T