When it comes to electrical work, whether you’re wiring up solar batteries, working on an RV setup, or just doing a car audio install, the job doesn’t end at crimping. What you use to seal and protect those connections is just as important. That’s where heat shrink tubing comes in.
But if you have shopped for some, you probably have seen two basic types: the heat shrink tubing kit (usually single-wall) and the dual-wall heat shrink.
So, which type do you use, and when?
Let’s keep this in basic, practical terms to help you make the right decision on your next project.
What Is Heat Shrink Tubing?
As the name suggests, heat shrink tubing is plastic tubing that shrinks tightly around a wire or connector when heat is applied. It helps:
- Insulate exposed wire
- Strengthen crimped terminals
- Protect against dirt, water, and wear
- Improve the durability and look of your work
It’s that finishing touch that takes your DIY wiring from “temporary fix” to “professionally done.”
But here’s the thing: not all heat shrink is the same.
What’s In A Heat Shrink Tubing Kit?
A heat shrink tubing kit, such as Selterm’s, is one box with heat shrink tube in different colors in varying sizes. These are usually single-wall tubing; it shrinks down when heat is applied, and there is no adhesive inside.
Best For:
- Basic wire insulation
- Indoor or dry-environment use
- Color-coding wires
- Small-scale electrical jobs
- General cable management
If you’re organizing wires in an RV panel, wrapping a crimped copper lug, or just tidying up connections, this is your go-to solution.
What Is Dual Wall Heat Shrink?
Now here’s the next level: dual wall heat shrink.
This tubing has two layers:
- The outer layer: same as regular heat shrink, durable polyolefin
- The inner layer: a heat-activated adhesive that melts and bonds to the wire or terminal
Once shrunk, this adhesive fills gaps and creates a watertight, airtight seal around your connection.
When Should You Use Dual Wall Heat Shrink?
If your project involves exposure to moisture, dirt, vibration, or corrosion, dual wall is the way to go.
Ideal For:
- Marine and boat wiring
- Solar installations are exposed to the weather
- Battery terminals in golf carts or RVs
- Automotive under-the-hood connections
- Any crimped terminal in a rough environment
It’s slightly bulkier than standard tubing, but it gives you next-level durability and peace of mind, especially in outdoor and high-vibration applications.
Can You Use Dual Wall For Everything?
Technically, yes. But should you?
Not always.
Here’s why:
- Dual wall is more expensive
- It’s less flexible and can be overkill for light-duty work
- It requires more heat and a steady hand to apply cleanly
So, for a wiring job like just organizing cables behind a panel, or even wrapping a small wire splice indoors, single-wall from the heat-shrink tubing kit is usually the better, easier option.
Side-By-Side Comparison
| Feature | Heat Shrink Tubing Kit (Single Wall) | Dual Wall Heat Shrink |
| Protection | Basic insulation | Waterproof & weatherproof |
| Flexibility | High | Moderate |
| Ease of Use | Very easy | Requires more heat |
| Best For | Dry, indoor, everyday wiring | Harsh environments, outdoor installs |
| Adhesive | No | Yes – built-in glue lining |
Quick Tips For Using Heat Shrink Like A Pro
- Always pre-cut and slide your tubing on before crimping
- Use a heat gun, not a lighter (you’ll get even, clean shrinkage)
- For dual-wall tubing, watch for adhesive to ooze slightly; that’s when it’s sealed
- Use clear tubing when you want to see labels or connection points beneath
- Double-check the tubing diameter before you start: it should fit over the wire and connector before shrinking
Why Choose Selterm’s Heat Shrink Tubing Kit?
Selterm’s kit isn’t just another box of tubing; it’s curated with real-world projects in mind. Whether you’re a DIYer working on solar, marine, RV, or off-grid builds, it’s the kind of kit that saves the day when you need it most.
- High-quality, flame-retardant material
- A variety of lengths, sizes, and colors
- Reliable 3:1 shrink ratio
- Works great with Selterm’s copper lugs and terminals
- Compact, organized case for your workbench or travel kit
Looking for more rugged protection? Selterm also offers dual-wall heat-shrink tubing separately, perfect to pair with battery lugs in outdoor installs.
Final Thoughts: Pick Smart, Shrink Smarter
No matter the project, sealing your connections right makes all the difference. A heat shrink tubing kit is great for quick fixes, indoor jobs, and basic cable management. But when the environment gets tough, think water, dirt, or constant movement, dual wall heat shrink gives your work that extra layer of durability and protection.
Both have their use. It’s not about which one’s better, it’s about what your project really needs. Choose smart, and your connections will last as long as the system itself.
