Polyolefin marine heat shrink tubing has a shrink ratio of 3:1 and a temperature range to 250 degrees Fahrenheit, making it suitable for electrical, insulation and cable bonding. The 42-piece marine heat shrink tubing assortment includes 1/8 in., 3/16 in., 1/4 in., 1/2 in. and 3/4 in. diameter sizes. Protect your wiring from moisture and dirt with heat shrink tubing.