Innovation is our forte and manufacturer and supplier of all size Piston Seals from our side is a strong example of the same. Rubber Piston Seals or Piston Cup Ring are used in hydraulic cylinders for fluid sealing. They are internal to the cylinder head and seal against the cylinder bore, preventing fluid from flowing across the cylinder head. This allows pressure build up on one side of the piston, making the cylinder extend or retract. PU Coated Roller | Spider Coupling Pad | Polyurethane Lined Roller | Flush Bottom Valve Diaphragm | Diaphragm | Irrigation Valve Diaphragm | Tricolover Gasket | Piston Cup Seal