White Heat Shrink Tubing 2:1 Ratio | 0.8mm–80mm | Electrical Cable Sleeving

Select a diameter (unshrunk) that is at least 20–30% larger than the outer diameter of the object you want to cover. For example, if your wire measures 3mm, choose the 4mm or 4.5mm variant. After heat is applied, the tubing shrinks to approximately half its original diameter at a 2:1 ratio. When in doubt, size up rather than down — a slightly loose fit before shrinking is normal and expected.

A 2:1 shrink ratio means the tubing shrinks to approximately half its original (unshrunk) inner diameter when heat is applied. For example, a 10mm (≈3/8") unshrunk tube will shrink down to roughly 5mm (≈3/16"). This ratio is the most common for general electrical insulation and automotive wiring harness applications.

This tubing typically begins to shrink at around 70°C (158°F) and generally reaches full shrinkage at approximately 120°C (248°F). A heat gun is the recommended tool — move it slowly and evenly along the tubing to avoid scorching. Avoid open flames, which can cause uneven shrinkage or damage the material.

Yes. Once shrunk, this tubing generally provides good resistance to moisture, dust, and mild abrasion, making it well-suited for automotive wiring harnesses, outdoor cable runs, and light marine environments. For prolonged UV exposure or contact with fuels and chemicals, we recommend contacting us to confirm suitability before ordering.

Heat shrink tubing in this category typically offers dielectric strength suitable for low-voltage applications, generally up to 600V. It also provides mechanical protection against abrasion and acts as strain relief at solder joints and terminal connections. For high-voltage or industrial-rated applications, please contact us to confirm the exact specifications for your use case.

Measure the total length of cable or wire you need to cover, then add 10–15% extra for trimming and overlap at joints. For a single repair or small electronics project, 1m or 3m is typically sufficient. For automotive builds, workshop wiring, or bulk electrical work, the 10m, 20m, or 50m options offer better value per meter and reduce the need for reordering mid-project.

Yes. The diameter range of 0.8mm–80mm covers a wide span of wire gauges. As a general guide: 0.8–1mm suits very fine wires (typically AWG 26–30), 2–4mm suits medium signal and power wires (typically AWG 18–24), and 6–10mm suits heavier power cables (typically AWG 10–16). Always measure your wire's actual outer diameter before selecting a variant, as insulation thickness varies by manufacturer.

Yes. The tubing can be cut to any length with standard scissors or a utility knife before applying heat. In most cases, cutting is easiest when the tubing is at room temperature. Allow a small overhang (typically 2–5mm) beyond the end of the cable or connector to ensure full coverage after shrinking.