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. 316 (285001-) Hydrostatic Tractor (ALL ONAN) H1 318 (S.N. 432277-999000) (S.N. 010001-120000) H2 430 Lawn and Garden Tractor (S.N. ALL) H3 332 Lawn and Garden Tractor (S.N. 424355- ) H2 322 Lawn and Garden Tractor (S.N. ALL) H2
