Features: Ratio: 3:1 heat shrink tube it will shrink up to 33% of original rapid contraction to raise efficiency and can be used for the contraction protection on of irregular shape objects and at the same time solve the problem that the 2 :1 Ratio heat shrink tube is not tight enough after shrinking. Adhesive Lined & Dual Wall: The heat shrink tube with hot melt adhesive on the inner wall.It can be shrunk by heating with hot air gun.It is easy to use.After shrinking, the inner lining glue will completely seal the materials at the two ends of the connection, so as to achieve better waterproof and insulating Sealing effects Feature: Sealing, waterproof, strain buffering, outer self extinguishing ,Dual wall thickness, while maintaining flexibility, improves mechanical protection strength with good viscosity .Our heat shrink tubing it very soft and elastic can effectively retardant , excellent Insulation performance. Widely Used: Heat shrink tubes are mainly used for anti rust and anti-corrosion protection of wire connection solder joints and insulation treatment of wire ends, wire harnesses and electronic devices, surface protection of fitness equipment parts and steel structures, identification of other products of wire boxes, etc Description: Color: Black Material: Polyolefin Heat shrink ratio: 3:1 Operating Temperature: -131°C to + 257℉ Shrinkage Temp: 212℉(Fahrenheit) Full Shrinkage Temp: 230℉maximum Tensile strength: 10.4Mpa Dielectric strength: 15 kV / mm Flammability: Flame Retardant Package Included:1x Heat Shrink Tubing As your chooes