Helixal — Professional Heat Shrink Tubing
2 inch heat shrink tubing is the maximum standard size in the Helixal 3:1 dual-wall line, designed for the largest industrial cable bundles, large-diameter pipe protection, cable harness end sealing, and structural cable covering in demanding environments. Typical applications include mining cable protection sleeves, offshore marine cable transits through hull penetrations, large motor feeder terminal sealing, and heavy equipment cable assembly end caps where a 50.8mm bore is needed to slip over terminated cable assemblies. At 50.8mm expanded diameter, this tube accommodates very large conductor assemblies and recovers to approximately 16.9mm after full heat application. The 3:1 adhesive-lined construction is essential at this scale — without the inner liner, a sleeve would collapse loosely over large irregular bundles, leaving voids between conductors that admit moisture and contaminants. For indoor dry-area applications where waterproofing is not a requirement, the 2:1 standard is a lower-cost option in this size. The 2" size is specified for mining, offshore marine, and heavy industrial applications where both maximum coverage diameter and a fully sealed sleeve are required simultaneously.
Click any size to navigate · 20 ft per roll
SKU: B0D642VB9T · 2" (50.8mm) · 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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2 inch (50.8mm) is the biggest standard heat shrink size there is — the top of the range. In 3:1 dual-wall it expands to slide over the fattest cable bundles, MCM conductors, and large crimped lugs, then recovers to roughly 16.9mm onto a hot-melt adhesive core. If you are searching for "2 inch heat shrink tubing," you are almost always sealing something big and irregular — a harness breakout, a pipe-and-cable transition, or a battery-bank main lug — where nothing smaller will pass over the shoulder.
The number that matters is the expanded inner diameter: 50.8mm going on, recovering to about 16.9mm at full 3:1 shrink. That range covers 4/0 AWG cable and 250–400 MCM conductors, large multi-wire bundles, big ring and lug terminals, and 1–1.5 inch pipe, hose, and conduit ends. Because the recovered wall pulls down to roughly a third of the starting bore, the same piece clears a wide lug on the way on and still grips the cable jacket behind it once heated — the whole point of a 3:1 ratio at this size.
If your bundle or lug measures under about 38mm on its widest shoulder, step down to 1-1/2 inch (38mm) — you will get a faster, cleaner recovery and less wasted wall. Reserve 2 inch for the genuinely largest transitions, where you need every millimeter of that 50.8mm mouth to pass the assembly. There is no larger slip-on size above this; past 2 inch the job moves to wraparound repair sleeves rather than tubing.
| Covering | Expanded clearance | Recovered grip | Better size if smaller |
|---|---|---|---|
| 4/0 AWG + large lug | 50.8mm — ideal | ~16.9mm onto jacket | 1-1/2" if lug ≤36mm |
| 250–400 MCM conductor | 50.8mm — ideal | Seals onto insulation | — |
| Multi-wire harness breakout | Slides over bundle | Bonds the group | 1-1/2" for tighter bundles |
| 1–1.5 in pipe / hose end | 50.8mm — ideal | Conforms + seals | 1-1/2" for 1 in pipe |
Expanded ID 50.8mm · recovered ~16.9mm · 3:1 ratio. Size to the widest shoulder the tube must pass, plus 20–30% clearance — never to the bare conductor.
At 2 inch you are almost never insulating a straight wire — you are sealing a bundle breakout, a heavy lug, or a cable-to-pipe transition with big voids between the strands. A single-wall 2:1 tube can cover that, but it cannot fill it: the gaps between conductors, and the step down from a fat barrel to a thinner jacket, are exactly where water tracks in. On a main battery or feeder cable, that channel runs straight to the crimp.
The hot-melt liner in Helixal’s dual-wall flows at about 70°C and floods those voids, then bonds the sleeve to every surface it touches — jacket, barrel, and the air gaps between. That is what turns a 2 inch sleeve into a sealed, strain-relieved termination instead of a loose cosmetic cover. For the largest, highest-value cables on a boat, RV, or industrial panel, the adhesive core is the whole reason to buy 3:1 at this size.
A 50.8mm tube has a lot of wall to move. Use a full-size heat gun on high (or a soft propane flame kept moving) — an undersized gun cools faster than the polyolefin recovers and you get a wavy, half-shrunk sleeve.
A big lug or cable bundle is a heat sink. Warm the metal and the bundle first, then bring the heat back to the tube, so the adhesive bonds to the heavy side instead of setting on the jacket first.
Start mid-tube and drive air toward both ends. Over a fat, irregular bundle a trapped air pocket leaves an open channel straight through the seal — the failure mode this size is most prone to.
Stop each end when a bead of clear adhesive appears. At this wall thickness it takes longer than a small tube — no bead means the liner never flowed and the void is still open.
The 2 inch roll is 20 continuous feet, cut to length — no offcut waste. At a typical 5-inch large-cable termination that is roughly 48 sealed ends; at longer 8–10 inch bundle breakouts, closer to 24. Because this is the size you reach for only on the biggest connections, a single roll usually covers a full battery-bank build, a shore-power refit, or a run of industrial cable terminations without reordering.
Keep reading →Heat Shrink Size Calculator · Size Chart & Selection Guide · Best Heat Shrink for Marine Wiring · Heat Shrink Tubing: Complete Guide
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.
Use a heat gun at 120°C or higher. 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 2" tube at full expanded diameter (50.8mm) 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.
Color-codes 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
