Parafilm M is a semi-transparent, flexible thermoplastic film with two-way stretch that delivers a tight moisture barrier seal for laboratory use. It clings securely to glassware and irregular surfaces and maintains its hold even during off-gassing. Odorless, colorless, and non-toxic, it is free from plasticizers and primarily composed of polyolefins and paraffin waxes for dependable resistance to many acids, alkalis, and some organic solvents. Engineered to stretch over 200% of its original length, Parafilm M helps prevent moisture and volume loss while reducing the risk of tampered data.