Flexible, thermoplastic, rolled, waterproof sheet interwound with paper to prevent adhering. Semi-transparent, almost colorless, odorless and tasteless. Supplied in 0.005" thickness. Adheres quickly and firmly to itself, covering culture tube or flask mouths and sealing petri dish edges. Excellent resistance to air, other gases, alcohol, common acids and moderately concentrated alkalies. At 70°F, it stretches 200% and returns partially to its original size. At 180°F to 200°F, it softens enough to make an adhesive bond between papers, cloths, leathers, etc. Supplied in dispenser cartons.