A coated rubber stopper is a type of laboratory stopper used to seal containers, such as flasks or test tubes. The rubber stopper provides a tight, air-tight seal to prevent contents from spilling or evaporating, while the coating provides additional protection against chemicals or other substances that may react with the rubber. The type of coating can vary, with options such as silicone, polytetrafluoroethylene (PTFE), or polyethylene, among others. The choice of coating depends on the specific application and the materials being stored or transported in the container.
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