Blue 2:1 Heat Shrink Tubing — 7mm to 300mm Diameter, 1m to 10m Lengths

Measure the outer diameter of the object you want to cover. The tubing's recovered (inner) diameter — shown as Φ in the variant name — should be slightly smaller than your object's diameter for a snug fit. For example, if your cable is 12mm wide, choose a variant whose recovered Φ is close to 12mm. In inches: 12mm ≈ 0.47". When in doubt, size up one step so the tube slides on easily before shrinking.

A 2:1 shrink ratio means the tubing will shrink to approximately half its original supplied diameter when heat is applied. For example, a 50mm (Φ 32mm) tube will recover to roughly 25mm inner diameter — or about 1.97" to 1.26" — conforming tightly around the object inside.

Polyolefin 2:1 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 typically sufficient. Move the heat gun steadily along the tube to avoid hot spots. Avoid open flames, which can scorch or unevenly shrink the material.

This tubing is generally made from flame-retardant polyolefin, which resists ignition and self-extinguishes. It is typically suitable for dry and mildly damp environments. For prolonged outdoor exposure or direct water contact, an adhesive-lined (3:1) heat shrink variant provides better sealing. Contact us to confirm specific environmental ratings for your application.

This tubing is compatible with a wide range of wire gauges, cable bundles, butt connectors, ring terminals, and solder joints. Match the supplied diameter to the object's outer diameter — the recovered Φ value shown in each variant tells you the final inner diameter after shrinking. It works with copper, aluminum, and most insulated conductors commonly used in automotive, marine, and residential wiring.

Yes. The tubing is sold in continuous lengths (1m, 2m, 5m, or 10m) and can be cut to any length with scissors or a utility knife. Cut before shrinking for the cleanest result — cut at a right angle to prevent the end from curling unevenly. You can also trim after shrinking if needed.

The first number in the variant name (e.g., 50mm) is the supplied inner diameter — the size of the tube before heat is applied. This must be larger than your component so the tube slides on freely. The Φ value (e.g., Φ 32mm) is the recovered inner diameter after full shrinkage. Always check the Φ value to confirm the tubing will grip your component tightly once shrunk.

Once recovered, polyolefin heat shrink tubing provides firm abrasion resistance, insulation, and strain relief. It is not a structural load-bearing component. For high-vibration or high-pull-force applications, secure cables with additional clamps or cable ties in addition to the heat shrink sleeve.