Ecoolbuy 225-Piece 18 Sizes O-Ring Assortment Rubber Washer Seals Watch Gaskets Set with a Re-Sealable Plastic Box 18 different sizes, 225 pieces in one portable storage case Flexible seal is easy to install for you No pollution, no radiation, no abnormal smell, environmental friendly Rubber oil seal is designed for hydraulic equipments use, high tear, temperature and corrosion resistance Widely used in automobile, mechanical equipment, engineering machinery, chemical, ship, hydropower station, aviation field, can be used for equipments like pump, hydro-cylinder or other hydraulic application that need to seal, to avoid leakage and make the machines work for long time