Orange Heat Shrink Tubing φ1mm–φ50mm | 2:1 & 3:1 Ratio | Wire & Cable Insulation

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. For example, if your wire bundle is 4mm (≈5/32") across, a φ5mm tube generally provides a snug fit after shrinking. When in doubt, size up — you can always apply more heat to tighten the fit.

A 2:1 ratio means the tubing shrinks to half its original diameter when heat is applied — suitable for most standard wire splices and terminals. A 3:1 ratio shrinks to one-third of its original diameter, making it ideal for irregular shapes, large connectors, or applications where a tighter, more conforming seal is needed.

Polyolefin heat shrink tubing typically 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 generally sufficient. Avoid open flames, as uneven heat can cause scorching or uneven shrinkage.

This polyolefin tubing is generally resistant to moisture, UV exposure, and mild chemicals, making it suitable for outdoor wiring repairs and marine environments in most cases. For fully waterproof connections, consider pairing it with adhesive-lined (dual-wall) tubing variants. Contact us to confirm suitability for your specific application.

Yes. This heat shrink tubing is commonly used for automotive wire harness repair, terminal insulation, and connector protection. The flame-retardant polyolefin material is generally rated for the temperature ranges found in engine bays and interior wiring. Always verify the operating temperature of your specific application before installation.

For single wire splices or terminal ends, 1M (≈3.3 ft) is typically sufficient for multiple connections. For wiring harnesses, panel builds, or larger DIY projects, 2M (≈6.6 ft) or 5M (≈16.4 ft) rolls offer better value and reduce the need to reorder. We recommend buying one size up from your estimated need to account for trimming and mistakes.

The range of diameters — φ1mm through φ50mm — covers wire gauges from very fine signal wires (typically 28–30 AWG at the small end) up to large power cables and conduit bundles at the larger sizes. Select the diameter based on the outer diameter of your wire or bundle, not the wire gauge alone, as insulation thickness varies by manufacturer.