Heat Shrink Tubing φ14–φ20mm | 7 Colors | Polyolefin 2:1 Ratio | 1m / 2m / 5m

Select a tube diameter that is generally 20–30% larger than the outer diameter of the wire or connector you need to cover. For example, for a 10mm cable bundle, a φ14mm tube typically provides a good fit before shrinking. After applying heat, the tube shrinks to approximately half its original diameter at a 2:1 ratio. When in doubt, size up — a slightly larger tube is easier to position than one that's too tight to slide over the connector.

This heat shrink tubing uses a 2:1 shrink ratio, meaning it shrinks to approximately half its original inner diameter when heat is applied. For example, φ14mm (≈0.55") shrinks down to roughly 7mm (≈0.28"), and φ20mm (≈0.79") shrinks to approximately 10mm (≈0.39"). Some longitudinal shrinkage may also occur, so cut your pieces slightly longer than needed.

Polyolefin heat shrink tubing generally begins to shrink at around 70–90°C (158–194°F) and fully recovers at approximately 120°C (248°F). A heat gun set to low or medium is the recommended tool for even, controlled shrinkage. An open flame can be used cautiously but may cause uneven shrinkage or surface scorching if held too close.

Standard polyolefin heat shrink tubing provides basic moisture resistance and is generally suitable for light outdoor use such as garden lighting wiring or trailer connections. However, it does not form a waterproof seal on its own. For fully waterproof or submersible applications, adhesive-lined (dual-wall) heat shrink tubing is typically recommended instead.

Compatibility depends on the outer diameter of your wire bundle or connector, not the wire gauge alone. As a general guide: φ14mm suits cable bundles with an OD up to approximately 7mm after shrink; φ20mm suits bundles up to approximately 10mm after shrink. Always measure your cable's outer diameter with calipers before selecting a size, especially for multi-conductor bundles or connectors with boots.

Yes. Polyolefin heat shrink tubing is widely used in automotive wiring harness repairs, connector insulation, and wire bundling. It is generally resistant to oils, fuels, and common automotive fluids, making it a practical choice for under-hood and chassis wiring applications. The color options also make it useful for color-coding circuits during restoration or custom builds.

Use sharp scissors or a utility knife on a flat surface for the cleanest cuts. Cut each piece 5–10mm longer than the area you need to cover to account for any longitudinal shrinkage during heat application. For high-volume jobs, a tube cutter or rotary cutter can speed up the process and produce more consistent lengths.