Description Muffler, round. 1-3/4" inlet ID, 1-3/4" outlet OD, 39" OA length, 4-1/4" diameter. Tractors: MF135 Perkins (s/n 9A99582 & up), MF150 Perkins (s/n 9A107187& up). This item is a suitable alternative for the following: 539525M91, TX12624, MF31, MF-31, A539525M91, A-539525M91, 522589M92, 522589M91, 30059V91, 10311A91