Description Vertical muffler for gas tractors. Fits engines C291 and C301. Inlet I.D. 2-15/16", outlet O.D. 3", length 34", diameter 6" round body. Tractors: 756, 2756, 856, 2856. Diesel engine D407, models 856, 2856. This item is a suitable alternative for the following: 398511R1, A139055, IH-19, IH19, 398511R91