1-1/2 inch heat shrink tubing is designed for very large cable assemblies, industrial conduit terminations, large pipe identification, and heavy-duty cable bundle end sealing where maximum coverage diameter is required. Typical applications include sleeving over large shore power cable assemblies, sealing industrial motor feeder entries at weatherproof enclosures, and covering cable tray exits through fire-rated walls where 38mm bore is the minimum workable dimension. At 38mm expanded diameter, this tube accommodates large cable bundles and multi-conductor assemblies and recovers to approximately 12.7mm after full heat application. The 3:1 adhesive liner is critical at this size — it provides the conforming seal around large, non-circular cross-sections when multiple cables are covered simultaneously, flowing into voids that a non-adhesive sleeve cannot seal. For dry indoor conduit end-cap or labeling applications where waterproofing is not required, the 2:1 standard is a lower-cost option in this size. The 1-1/2" size is the standard for sealing conduit risers, protecting cable entry points on outdoor switchgear, and covering large pipe-and-cable assemblies in process plant environments.
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SKU: B0D649MTCL · 1-1/2" (38mm) · 20 ft
Complete dual-wall adhesive performance in a bulk roll format. Permanently waterproof, 600V rated, and rated for the harshest environments.
Sizing over a connector? The Wire Gauge row above is for bare conductor. Heat shrink must be sized to the widest point it passes over, so a crimped butt splice or lug barrel needs a larger tube than the wire alone — a 22–18 AWG splice barrel measures 5–6mm, a 16–14 AWG barrel 7–8mm, and a 12–10 AWG barrel 9–11mm. Measure the barrel, allow about 20% clearance, and confirm the recovered diameter is smaller than the narrowest thing the tube must grip. Use the size calculator.
High quality and amazing value for the price
I'll never buy individual bags of heat shrink tubing again. This is very high quality with a shrink ratio that is truly amazing (all of the tubing from this company is). I wonder if I'll be able to use this entire roll in 10 years!
Good quality and sealing heat shrink
Heat shrink works good. Bought this for work. Makes a nice sealed wire connection. Good quality, better than pre cut heat shrink, you can make whatever length you want.
I LIKE THIS!
I solder, and heat shrink, all of my automotive electrical connections. This is a great product, and I can cut it to any length. The price is great, and the shipping was fast!
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1-1/2 inch (38mm) passes over fully terminated cable assemblies and large lug connections up to roughly 30mm, recovering to about 12.7mm. It is the size used at shore power inlets, main inverter feeds and industrial cable ends — terminations too large for 3/4 inch and too important to leave merely covered. Above this diameter the practical constraints shift, which is worth knowing before ordering.
Recovery is driven by the temperature of the polyolefin itself, not by the temperature of the air leaving the gun. A 38mm tube has both more material and more surface area losing heat to the surroundings, so it takes appreciably longer to bring the whole circumference up to temperature — and the far side cools while the near side is being heated.
Rotate continuously and work in passes rather than trying to finish one area. A useful check is that the tube should be recovering evenly all the way round before any part of it is fully down. If one side is tight while the opposite side is still loose, the heat is too concentrated and the finished joint will carry a wrinkle line along the cold seam.
The adhesive adds a second requirement. The liner sits behind the full wall thickness, so it reaches flow temperature last. Full recovery of the outer wall is not the finish line — the finish line is a bead of adhesive appearing at the ends. On a 38mm tube that takes noticeably longer than an installer used to smaller sizes expects.
| Property | Figure | Why it matters |
|---|---|---|
| Expanded diameter | 38mm (1-1/2") | Passes over terminated assemblies up to about 30mm |
| Recovered diameter | ≈12.7mm | Grips a large cable jacket behind a lug or gland |
| Typical application | 3/0–4/0 feeds, shore power assemblies | Terminations too large for 3/4 inch |
| Heating | Rotate continuously, multiple passes | Even circumference recovery before any point goes fully down |
| Seal indicator | Adhesive bead at both ends | The liner flows last, behind the full wall thickness |
| Roll length | 20 ft | Three to five large terminations, or two to three penetrations |
If one side is tight while the other is still loose, the heat is too concentrated — the finished joint will carry a wrinkle along the cold seam.
Move to 2 inch, which has a 50.8mm bore and recovers to roughly 16.9mm. At these diameters clearance disappears faster than the numbers suggest.
A 12.7mm recovered wall will not grip it. Either step down a size or accept that the tube is a cover rather than a seal at that end.
For strain relief and identification indoors, the 1-1/2" 2:1 on 60ft is the appropriate product and materially cheaper per foot.
The 20ft roll is stock for someone doing this work repeatedly. One shore power inlet replacement is better served by the 10ft short pack.
Keep reading →2" 3:1 Dual Wall — the largest in the line · 1-1/2" 3:1 Dual Wall — 10ft short pack · Marine Heat Shrink Tubing
Verify the expanded diameter is 20–30% larger than your wire or connector. The tubing must slide freely before heat is applied — if it drags, go one size up.
Cut to length and thread onto the wire or cable before making the splice or crimp. Overlap each terminal or connector end by at least 10mm for a proper seal.
The tubing starts shrinking at 100°C, but the adhesive liner only flows at 120°C — so keep the heat gun moving past the point where it looks shrunk. Start at the center and work outward to push air toward the ends. Adhesive will appear at the tube ends — that is your visual seal indicator.
The tubing should be tight and uniform with adhesive visible at both ends. No gaps, lifting, or cold spots. Pull-test the finished connection to confirm the adhesive bond.
Actual 1-1/2" tube at full expanded diameter (38mm) and after heat recovery. Use this as your fit reference before cutting.
Seals the entry point of cable bundles through bulkheads, firewalls, and conduit fittings against moisture, dust, and vapors.
Provides insulation and end sealing on large industrial conductors in switchgear, motor control centers, and distribution equipment.
Seals conduit ends and cable transition points in outdoor electrical installations against water ingress and UV degradation.
Band-marks and mechanically protects large pipe, hose, and cable assemblies in process plants, mining, and heavy industry.
Provides a degree of flame barrier at bulkhead and firewall penetrations for large cable bundles in industrial and marine applications.
Applied at panel entry and exit points to distribute bending stress and prevent jacket damage on large-diameter industrial cables.
Recovered diameter is approx. 1/3 of the expanded size shown · All sizes ship to USA & Canada
