OEX ACX1297 Heat Shrink Dual Wall Black ID: 39mm Length: 300mm - 4 Pce

OEX ACX1297 Dual Wall Adhesive-Lined Heat Shrink Tubing 39mm Internal Diameter Black 300mm Lengths Pack of 4

The OEX ACX1297 is a dual wall heat shrink tube in black, supplied as four 300mm lengths with a 39mm internal diameter before shrinking. Constructed from polyolefin with an inner adhesive lining, it provides both mechanical protection and a waterproof seal when applied. The outer polyolefin layer shrinks to grip the cable or connector while the inner adhesive melts and flows to fill gaps and create a moisture-resistant barrier. Shrink ratio is 3:1, shrink temperature is 110°C, and the operating range is -55°C to +105°C. Covered by a one year warranty.

Product overview

Standard single wall heat shrink provides mechanical protection but does not seal against moisture ingress. The dual wall construction of the ACX1297 adds an inner adhesive lining that melts when heat is applied, flowing around the cable or connector to fill any gaps and create a weatherproof seal at the join or termination. This makes it suited to applications where moisture, humidity or water exposure is a concern marine wiring, outdoor exposed runs, battery cable terminations, and underbonnet joins where water ingress would cause corrosion or electrical faults over time.

The 3:1 shrink ratio means the 39mm ID before shrink reduces to approximately 13mm, giving a wide working range of cable and connector sizes from a single piece. Each pack contains four 300mm pieces, totalling 1.2m, sized for individual joint and termination applications rather than continuous harness covering. The shrink temperature of 110°C allows activation with a standard heat gun at a relatively low setting without risk of damage to surrounding wiring or connectors. The operating range of -55°C to +105°C covers the full range of automotive, marine and outdoor environments including cold-climate starts and sustained underbonnet heat.

Features and benefits

Dual wall construction with adhesive inner lining: The polyolefin outer layer shrinks to grip the cable or connector while the inner adhesive melts and flows to fill gaps, creating a mechanical grip and moisture-resistant seal in a single application.

3:1 shrink ratio: Shrinks to one third of the supplied 39mm internal diameter, down to approximately 13mm, accommodating a wide range of cable and connector sizes from a single piece.

39mm internal diameter before shrink: Suits large cables, connectors and terminal ends, making it practical for battery cable terminations, large connector sealing and heavy harness joints.

300mm lengths, pack of 4: Four pieces per pack for individual joint and termination applications, totalling 1.2m per pack.

Shrinks at 110°C: Activates with a heat gun at a low temperature setting, reducing the risk of damage to surrounding wiring and connectors during application.

-55°C to +105°C operating range: Covers cold-climate automotive and marine use through to sustained underbonnet operating temperatures.

Black: Standard colour for automotive wiring applications.

Polyolefin with adhesive lining: Industry-standard material combination for weatherproof heat shrink applications in automotive and marine environments.

One year warranty: Covered by a one year OEX warranty.

Technical specs

Frequently asked questions

What is dual wall heat shrink and how does it differ from standard heat shrink? Standard single wall heat shrink provides a mechanical sleeve that grips the cable or connector when heated but does not seal against moisture. Dual wall heat shrink adds an inner adhesive lining that melts during application, flowing around the cable to fill gaps and create a weatherproof seal. The result is both mechanical protection and moisture resistance from a single piece, suited to marine, outdoor and underbonnet applications where water ingress is a concern.

What is the shrink ratio and what does it mean for cable sizing? The 3:1 shrink ratio means the tubing shrinks to one third of its original diameter when heated. The ACX1297 has a 39mm internal diameter before shrink, reducing to approximately 13mm after. This gives a wide working range, covering cables and connectors up to approximately 39mm diameter in a single piece.

What tool do I need to apply this heat shrink? A heat gun set to the appropriate temperature is the recommended tool for applying heat shrink. Avoid open flames as they can cause uneven shrinking or damage to the tubing. The ACX1297 shrinks at 110°C, which is achievable with most standard heat guns at a low to medium setting.

Can this heat shrink be used in marine environments? Yes. The adhesive inner lining creates a moisture-resistant seal when applied correctly, making the ACX1297 well suited to marine wiring applications where water ingress at joins and terminations is a concern.

Is this product available in other sizes? OEX produces dual wall heat shrink in a range of diameters. Contact us for available sizes to suit your specific cable and connector dimensions.