Innovation is our forte and manufacturing, trading, exporting, importing along with supplying of all size Piston Seals from our side is a strong example of the same. Rubber Piston Seals or Piston Rings 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.