Prime Line 7-03680 Muffler Replacement for Model Kohler 237550 Cub Cadet 393840-R91 Fits Models K241, K301, K321 (7, 10, 12 HP) 3 1/2" OD x 1 3/8" ID (inlet) x 1.332" Hole Size 16 1/8" Overall Length 11 3/4" Canister Length