Shrink tubing, or heat-shrink tubing, is a shrinkable plastic tube used to insulate wires. Shrink tubing protects wires from abrasion and other damage, and provides environmental sealing for stranded and solid wire, conductors, connections, and terminals.
Shrink tubing is ordinarily made of nylon, which shrinks radially and not longitudinally when heated. This reduces the tube's diameter without affecting the overall length of the tube. The nylon can be treated with chemical additives, and manufactured thicker or thinner, to meet the requirements for most environment demands.
Shrink tubing is fitted to wires and slid over connections before shrinking. Using this method, shrink tubing can be used to repair insulation, bundles wires together, and seal connections. It is available in a wide variety of colors to aid with cable management, and some designs may include adhesive on the inside of the tube to provide a better seal.