Clear 2:1 Heat Shrink Tubing — Electrical Sleeving for Wire & Cable

Measure the outer diameter of the wire or connector you need to cover, then select a tubing size whose expanded (pre-shrink) inner diameter is at least 10–20% larger than that measurement. After shrinking at the 2:1 ratio, the tubing will grip the wire snugly. For example, a 4mm wire typically works well with 5mm or 6mm tubing. When in doubt, size up — you can always apply more heat to shrink further, but you cannot expand tubing that's too small.

Polyolefin 2:1 heat shrink tubing generally activates at temperatures starting around 70–90°C (158–194°F) and fully shrinks at approximately 120°C (248°F). A heat gun set to low or medium is typically sufficient. Move the heat gun slowly along the tubing from one end to the other for even shrinkage. Avoid concentrating heat in one spot, and avoid open flames where possible to prevent uneven or scorched results.

Polyolefin heat shrink tubing in this category is generally manufactured to meet flame-retardant standards (typically UL 224 or equivalent). It will self-extinguish when the heat source is removed in most cases. If your application requires documented compliance certifications, please contact us before ordering so we can confirm the specific rating for the batch you receive.

Standard clear polyolefin heat shrink tubing provides good moisture resistance once fully shrunk, making it suitable for many outdoor and damp-location applications such as marine wiring and exterior automotive connections. However, it is not a waterproof adhesive-lined tube — water can potentially wick in from the open ends. For fully waterproof sealing, consider adhesive-lined (3:1 or 4:1) heat shrink tubing instead. Contact us if you need guidance on the right product for your environment.

As a general guide for this clear 2:1 heat shrink tubing: 0.8–1mm tubing typically fits 28–24 AWG wires; 1.5–2mm fits 22–20 AWG; 2.5–3mm fits 20–18 AWG; 3.5–5mm fits 16–12 AWG; 6–8mm fits 10–8 AWG; 10–12mm fits 6–4 AWG; 14–18mm is generally suited for larger cables, conduit bundles, or connector boots. Always measure your specific wire's outer diameter before ordering to ensure the best fit.

Clear heat shrink tubing lets you see wire color codes, printed labels, and markings through the sleeve after installation — a significant advantage for color-coded wiring harnesses, labeled connectors, and PCB assemblies where visual inspection is needed without removing the sleeve. It's also commonly used in applications where aesthetics matter and the underlying wire or component should remain visible.

Cut the tubing approximately 10–15mm (about 1/2") longer than the area you need to cover on each end. Heat shrink tubing also shrinks slightly in length (typically 5–10%) when heated, so the extra length compensates for longitudinal shrinkage and ensures full coverage of the splice or connector. For terminal crimps, a 20–25mm (≈1") piece is generally sufficient for most wire gauges.