Standard polyolefin heat shrink sleeving, also known as single wall, is available in many colours and supplied on large reels or mini-spools. Usually supplied in a 2:1 shrink ratio but also available in 3:1 for situations where there is a larger discrepancy between the two parts to be covered or the sleeve has to be passed over an existing component first. The use of polyolefin heatshrink sleeving to insulate, support and identify wires is common practice in most electrical assemblies. Packaging options are large reels, as shown, or mini-spools. For harsh environments or higher specifications please see the high performance heat shrink sleeving section.