:The HellermannTyton 309-32543 is a multi-purpose 2:1 heat shrinkable tubing. It is a flexible, high-shrink ratio, transparent tubing. It is made of a durable material that has excellent electrical and mechanical properties. The tubing has a 25.4mm diameter when in its free state, however, it can be reduced to a 12.7mm diameter through the application of heat. This makes it ideal for sealing, insulating, strain relief, protecting, bundling and color coding of wiring components. The tubing provides a strong, yet removable, physical connection between the applied components and offers excellent protection from corrosion. It provides a secure water tight seal and abrasion resistance for all wiring components.