is a type of electrical insulation and protection that is used to shield electrical wiring, moisture, oils, and other contaminants from damaging the conductor, joint, or other components. The tubing is made from advanced polymer materials, and is designed to shrink uniformly when heated for a tight fit around the application. When properly applied, it helps protect electrical conductors and provides a neat, stress-free and waterproof insulation for electrical bands, cables, connectors, and other components. The 40/13 measurement refers to the wall thickness before heating and the wall thickness after heating. The 333-34000 is a pre-cut heat shrink sleeve specifically designed for a 6" F connector application. This pre-cut hollow heat shrink sleeve is designed to fit over the male connector and extend over the connector body and barrel to cover and protect the entire connector against environmental and physical damage. The black color option is ideal for shielding cables and cable harnesses from electromagnetic interference (EMI).