In this article
The basic rule: size and chain type
A Size 5 coil slider does not automatically fit a Size 5 metal zipper. A swap only works when both type and size match. Molded teeth need a wider channel, so a coil slider will not fit them.
How to identify a slider size
- Check the back of the slider, where the size is often stamped.
- That figure may be a mould number rather than a size.
- Close the zipper and measure the width of the teeth with a ruler.
- Letters on the slider can also indicate the type.
What happens with the wrong slider?
- The slider moves but the teeth do not close.
- It runs heavily or jams.
- Teeth or slider wear out over time.
Do sliders fit across brands?
There is no general compatibility table. When a zipper will not close, manufacturers first advise checking that slider and chain come from the same supplier and are the same size. In production, the safest route is to source them together. MAK Zipper sells all slider and puller types in metal and plastic.
Material compatibility
A hard copper-alloy slider is not recommended on aluminium teeth, as it can damage them.
How to check compatibility before ordering
- Identify the chain type: Separate metal teeth, separate plastic teeth or a continuous spiral.
- Measure the closed width: Measure across the closed teeth.
- Check the slider's markings, but do not rely on them alone.
- Send your supplier a sample: Share a piece of the chain if you can.
- Try the new slider: Check the teeth close properly behind it.
Slider fit by type
| Chain | What to check |
|---|---|
| Metal | A slider made for metal; material match on aluminium teeth |
| Coil | A slider made for coil |
| Molded plastic | A wider-channel slider for this type |
| Invisible | A dedicated invisible zipper slider |
| Continuous chain | Bought separately; size and type must match |
Why might a new slider not solve it?
If the teeth are crushed or broken, or the tape is worn, a new slider may not be a lasting fix. The problem can also persist if the two sides of a coil have different twist directions or a seam narrows the slider's path. The whole zipper may then need replacing.
Advice for volume production
Sourcing slider and chain from one supplier, in the same size, reduces compatibility problems. Run a small trial before mixing batches, and keep the approved sample as a reference.
Frequently asked questions
Does every Size 5 slider fit every Size 5 zipper?
No. The chain type must match as well as the size, and fit across manufacturers is not guaranteed.
Is the number on a slider the zipper size?
Often, but it can also be a mould number. Measuring the teeth is safer.
Can I use a slider from another brand?
It sometimes works, but there is no general compatibility table. Test before using it in production.
The slider moves but the teeth will not close. What now?
First check the size and chain match. If the slider is worn, replace it with a suitable new one.
