We are offering here the Rubber Stoppers that are 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. They are preferable for applications that require a tighter seal or a greater degree of chemical resistance. The stoppers are small pieces of rubbers that are used for various purposes. Moreover, some rubber stoppers are used in several machines that have sharp endings. They are used in chemical laboratory in combination with flasks and test tube and also for fermentation in winery.