Marine Grade Heat Shrink Tube Dual Wall Heat Shrink Tubing Glue Inside Fast Wrap

Measure the outer diameter of the largest part you need to cover — typically the connector body or the thickest point of the bundle. Select a tubing size whose expanded (pre-shrink) diameter is at least 10–20% larger than that measurement. With a 3:1 ratio, the recovered diameter will be one-third of the expanded size, so there is generous margin for irregular shapes. When in doubt, size up one step rather than down.

A heat gun set to 90°C–120°C (194°F–248°F) is the most controlled option and is recommended for field use. Keep the nozzle moving in a slow, even pass from the centre outward to avoid trapping air bubbles. An open flame such as a lighter can be used in a pinch but risks scorching the outer sleeve or uneven adhesive flow. Do not use a standard hair dryer — it does not reach the temperatures needed to activate the inner glue layer.

When correctly applied, the melted adhesive liner creates a watertight seal around the conductor that resists moisture ingress, salt spray, and fuel splash — making it suitable for marine and automotive environments. It is not rated for continuous full submersion at depth without additional sealing measures. For bilge wiring or permanently submerged runs, pair with a waterproof connector and additional sealant at the entry point.

Yes. The hot-melt adhesive bonds to aluminium conductors and connector bodies as effectively as to copper. Aluminium wiring requires clean, oxide-free surfaces for reliable electrical connections, so ensure the conductor is properly prepared before applying the tubing. The polyolefin outer sleeve does not react with aluminium oxide and will not accelerate corrosion.

Standard single wall tubing provides insulation and strain relief but leaves a small gap between the tubing and the conductor that moisture can wick through over time. Dual wall tubing adds an inner adhesive layer that melts during shrinking and fills that gap completely, creating a mechanical and environmental seal. This makes dual wall the correct choice for any application exposed to water, vibration, or corrosive atmospheres.

The Clear variant allows visual inspection of the conductor or splice beneath the tubing after installation — useful for quality checks or when you need to verify wire colour coding without cutting. Coloured variants (Black, Red, White, Yellow, Blue, Green, Orange) are used for circuit identification and to meet wiring colour standards in automotive, marine, and industrial applications. All variants share the same adhesive liner and shrink performance.

Yes. The tubing cuts cleanly with sharp scissors or a utility knife before heat is applied. Cut at a slight angle to reduce the chance of fraying. Once shrunk, the tubing can be trimmed with a sharp blade if needed, though the adhesive layer will have bonded to the conductor and trimming may expose the inner glue edge. Always cut to your required length before shrinking for the cleanest result.