The kit consist of all the serviceable seals in the cylinder. It is recommended to replace all the seals used in the cylinder if the cylinder is opened for any reason during its service life. Seal Kits contains either / or combinations of P.T.F.E., nitrile and polyurethane seals. These seals are suitable for use when hydraulic (mineral-type) oil is the operating medium. The seal kit in general will have the following seals depending on construction : Piston seal, Piston bearings, Orings, Backup rings, Rod seals & Wiper seal