530Pcs Heat Shrink Tubing Assortment in 11 Sizes and 6 Colors with Case. Electrical Sleeve of Polyolefin: Excellent insulation, wear and corrosion resistant performance. Resistance to the environment and safety: made of polyolefin, contraction ratio: 2: 1,15 kV / mm dielectric and flame retardant, soft and flexible, acid and alkaline resistance, anti-aging. Easy to use: exposed to heat source for a few seconds at 70 ℃. The sleeve wrap will quickly reduce at least 1/2 in diameter. Length: 45mm/pc, supplied internal diameter: 1.5mm,2.0mm,3.0mm,4.0mm,5.0mm,6.0mm,8.0mm,10.0mm.530Pcs Heat Shrink Tube suitable for electrical insulation, bundling of cables, color coding, mechanical protection, articulated cables and daily repairs, etc.