Nitto PVC 21 is a premium grade PVC tape coated with a rubber-based pressure sensitive adhesive tape used to insulate electrical wires and other materials that conduct electricity.
It can be made of many plastics, but PVC (polyvinyl chloride, "vinyl") is most popular, as it stretches well and gives an effective and long lasting insulation.
Use of electrical tape is not a permanent solution for repairs. Since electrical tape is rubber-based, it can break down over time and lose some of its stretch. Therefore, it's important to make sure its used promptly.
Can be used for color coding and bundling of many surfaces.