For use in electrical systems to repair, insulate and add strength to wiring Tubes shrink to half diameter when heated to provide a secure seal Includes 164pcs: 60pcs 1x40mm, 30pcs 2x40mm, 16pcs 3x40mm, 16pcs 4x40mm, 16pcs 6x40mm, 10pcs 8x80mm, 8pcs 10x80mm, 8pcs 14x80mm 5 colors: red, green, blue, yellow, black 70°C minimum shrink 125°C full shrink bulk package, no box Use a heat gun or lighter at about 1/2 inch distance to shrink the tube. Don't touch the tube until it is completely cool.