These o-rings are needed when your hydraulic control valve starts to leak around the spool on your John Deere Garden Tractor. One kit is needed for each spool. Your H1 will need one kit and your H3 will need 3 kits. Below is listed models this kit will fit.
140 ALL serial numbers ALL types of valves300 ALL serial numbers312 ALL serial numbers314 ALL serial numbers316 KOHLER ALL serial numbers317 ALL serial numbers318 serial numbers (285001 - 432276)