Rubber Tube Plugs
A rubber stopper is a small, tapered plug used to seal the openings of test tubes, flasks and other laboratory glassware. Stoppers made of cork are also available for this purpose. However, rubber stoppers are preferable for applications that require a tighter seal or a greater degree of chemical resistance.
The primary purpose of a rubber stopper is to prevent a gas or liquid from escaping its container. The main properties that make rubber suitable for use as a laboratory stopper are its elasticity, chemical resistance and impermeability.
