High-quality materials: Made of polyolefin and hot melt adhesive, waterproof, suitable for electrical insulation or insulation of open or connected wires. Comprehensive utility: Heat shrink tubing is very suitable for any workshop project, fixing broken cables, electrical insulation, connecting cable, etc. You can also use it for all charging cables and earphones for iPhone and iPad. Safe and easy to use: Heat shrink tubes have the advantages of good electrical insulation, good sealing and corrosion resistance, as well as high temperature resistance. Cover the bare wire part with these tubes, heat it with a soldering iron, heat gun or even a hair dryer (hot enough), the tube will shrink to protect the wires and give you a professional look of the repair work. Length: 45mm/90mm, Inner Diameter: 1.6mm/2.4mm/3.2mm/4.8mm/6.4mm/9.5mm, 2 Colors, 6 Sizes, 270pcs, 3:1 Shrink Ratio (Shrinks to 1/3 of the supplied diameter). What You Get: 6 Sizes, 2 Color 3:1 Shrink Ratio Heat Shrink Tubing, 270pcs in total. Shrinkage: 3:1 Temperature Class: 125C Voltage Class: 600V Color: Red, Black Delivered Quantity: 270 pieces/setbecomeveryrich