You will be buying one after market 6" Pivot Rod Kit for H or M  Farmalls. It is used on H & M seat that use a shock. This one is 6 inches, I also sell 3 1/2 inch pivot rods. Measure yours. It is not hard to install after the old is removed. Also fits Massey Harris 20, 33, 44 ,333, 444, 55, 555 and Mustang with velvet ride seat. It is new. T19118  T19119  T19120   230287