Loses it's diameter due to heating (up to 125°C/260°F). Can be used for wire isolation an marking.
Large tube on big cable or bunch of wires allows to write descriptions on it with waterproof marker.
Color standard allows easy search of necessary wire. The tube isolates voltage up to 600 V. Can be heated with fan, soldering
iron heater or gas lighter. There are variety of colors and diameters available on market, comes in 15-25 cm segments or in