3:1 Heat Shrink Tubing Non-Adhesive — Φ1.5mm to Φ50mm Electrical Wire Sleeving

Measure the outer diameter of your wire or bundle before shrinking. With a 3:1 shrink ratio, the tubing will recover to approximately one-third of its supplied inner diameter. As a general rule, choose a size where the supplied inner diameter is at least 20–30% larger than your wire's outer diameter to allow easy insertion, then confirm the recovered diameter will be snug. For example, Φ6mm tubing (≈0.24" supplied) typically recovers to around Φ2mm (≈0.08").

This tubing has a 3:1 shrink ratio, meaning it shrinks to approximately one-third of its original inner diameter when heat is applied. This is particularly useful for covering connectors, terminals, or irregular shapes where a tighter, more conforming fit is needed compared to standard 2:1 tubing.

Polyolefin heat shrink tubing of this type generally begins to shrink at around 90°C (194°F) and achieves full recovery at approximately 120°C (248°F). A heat gun is the recommended tool. Avoid open flames, as uneven heat can cause scorching or uneven shrinkage.

This is a non-adhesive (dry-wall) heat shrink tubing. It provides electrical insulation and mechanical protection but does not create a waterproof seal on its own. For outdoor or moisture-exposed applications requiring a watertight seal, adhesive-lined (dual-wall) heat shrink tubing is generally recommended instead.

As a general guide:

• Φ1.5mm — typically suits very fine wires (around 28–24 AWG)
• Φ3mm — typically suits 22–18 AWG
• Φ6mm — typically suits 14–10 AWG
• Φ9–12mm — typically suits larger cables or small connectors
• Φ15–24mm — typically suits multi-conductor bundles or medium connectors
• Φ30–50mm — typically suits large cable bundles or industrial connectors

Always verify by measuring your specific wire or bundle outer diameter before ordering.

Polyolefin heat shrink tubing of this type is generally RoHS compliant and is commonly used in automotive wiring harnesses, marine electrical systems, and industrial applications. For safety-critical or regulated installations, please contact us to confirm compliance documentation for your specific application.

Standard scissors or a utility knife work well for cutting polyolefin heat shrink tubing. For clean, square cuts on larger diameters (Φ18mm and above), a sharp blade or tubing cutter is recommended. Cut slightly longer than needed — typically 5–10mm extra on each end — to account for any end pull-back during shrinking.