Parafilm is a prouct of the Pechiney Plastic Packaging Company, consisting of a flexible film, available in several different lengths and widths. It is commonly used for sealing or protecting vessels (such as flasks or cuvettes). It is stretchable, moldable, waterproof, odorless, thermoplastic, semitransparent and self-adhering. It is also used to further seal a lidded container against moisture for long term storage.