Size 9 Pure Gum Rubber Stoppers will plug food containers, lab vials and other openings. Pure Gum Rubber useful to 220º F and in applications with moderate chemicals, alocohols and organic acids. Do not use with strong acids, fats, grease or hydrocarbons. Not for food or beverage packaging applications.
Replacing a set of these that I've used on a boat as scupper plugs. They've been exposed to the sun every day for about 5 years and were still working great. We now keep the old ones as spares.