3:1 SHRINK RATIO - Recovers to 1/3 of its diameter, and makes a tight seal. Eliminates the problem of 2:1 tubing not shrinking tight enough. GLUE INSIDE - When heat is applied, adhesive comes out and seals the connection, creating waterproof and long-lasting insulation. VARIETY OF SIZES - We have included 7 most commonly used diameters ranging from 3/32inch to 3/4inch. Shrink tubing is precut to 3.5 inches. EASY TO USE - heat shrink tube over your connection point and apply heat. Professional connections seconds. DUAL WALL TUBING - Outer wall provides abrasion resistance. Inner wall creates waterproof seal and strain relief. Heat shrink ratio: 3:1 Operating Temperature: -55 Celsius to + 125 Celsius Minimum Shrinkage Temp: 70 Celsius Full Shrinkage Temp: 110Celsius maximum Dielectric strength: 15 kV / mm : Flame Retardant When heat is applied, this wire shrink wrap tubing recover to a 1/3 of its diameter. Its high recovery ratio makes it possible to repair most damaged cable jackets