Muffler, vertical round body. Inlet is a 4 bolt mounting plate with a 2-1/2 inch ID, 7/16 inch bolt holes, and 3-7/16 inch bolt spacing between adjacent holes. 2-5/8 inch outlet OD, 21 inch overall length, 4-1/4 inch shell diameter, 14-1/2 inch shell length, 4-1/2 inch inlet length, 2-1/2 inch outlet length. Tractors: A, AR, AN, ANH (s/n 410000 & up); 60, 620, 70, 720. Replaces R21826R, R81826R.