You will find all kinds of different sizes and colours of heat shrink for your cables here. Heat shrink is usually used to insulate, protect and bind cables or wires together or to repair the insulation on a damaged cable. The heat shrink tubing is simply passed over the cable or cables and then shrinks to about half its size when it is heated using a tool such as a heat gun. Choosing adhesive-lined heat shrink will provide an even better seal against moisture penetration.