Size 4 Green Neoprene Rubber Stoppers are tapered Rubber Stoppers that will plug food containers, lab vials and other openings. Manufactured from Neoprene Rubber. Neoprene Rubber is suitable to a temperature of 275 degrees F and suitable for use with petroleum products, minerals, oils and fats.
For my outdoor fountain, work perfectly, exactly the right size. Thanks. Shipping was very reasonable.