Description Piston, hydraulic lift, less rings. 2-1/2" dia. (ring set part number 180898M1)Tractors: TE20, TO20, TO30, TO35 (prior to s/n 179304), F40, MH50. This item is a suitable alternative for the following: 181983M1, 181983M91, 9N530B, A577619, S.61588, S61588