In this article
How is it made?
Separate plastic teeth, usually made of a durable plastic called POM, are injection-molded directly onto the tape.
Where is it used?
Coats, sportswear, outdoor products and marine products are the most common uses.
| Feature | Molded | Coil | Metal |
|---|---|---|---|
| Teeth | Separate plastic | Continuous spiral | Separate metal |
| Flexibility | Stiff | Flexible | Stiff |
| Weight | Lighter than metal | Light | Heavier |
| Salt water | Does not rust | Rust-free teeth | Needs care |
Points to watch
- Ironing: Plastic teeth have a low heat limit. Manufacturer sources cite 130 °C.
- Extreme cold: Hard knocks at very low temperatures can break teeth.
- Slider: Molded teeth need a wider channel, so a coil slider will not fit.
When to choose it
Choose it when you want a light zipper with a chunky look, when the product is used outdoors, or when coloured teeth are part of the design. MAK Zipper also produces molded zippers.
Which sizes are available?
Manufacturer catalogues commonly list molded teeth in Sizes 3, 4, 5, 8 and 10, with larger sizes for special uses. Widths can differ slightly from metal zippers of the same number, and the exact width is confirmed on a sample.
What is it made of?
The most common material is POM (polyoxymethylene, or polyacetal). Polypropylene can be used for a smoother surface or clear teeth. Some names in the market are brands or material names, so "molded plastic teeth" is the clearest wording when ordering.
Products that use molded zippers
- Coats and parkas: For a chunky look and low weight.
- Sportswear: For coloured tooth designs.
- Outdoor products: For weather exposure.
- Marine products: Plastic teeth do not rust in salt water, but the slider material must suit it too.
Does it follow curved seams?
Its separate, stiff teeth follow curves less well than coil and work best on straight lines. For curved pockets or rounded corners, coil is usually easier to sew.
Care tips
- Follow the maker's ironing limit and do not press directly on the teeth.
- Avoid hard knocks in extreme cold.
- Rinse with fresh water after marine use and do not store it wet.
Frequently asked questions
Is a molded zipper better than a coil zipper?
It depends on the use. Molded gives a chunky look on straight lines, while coil is flexible and light.
Do molded plastic zippers rust?
The plastic teeth do not rust, but a metal slider can corrode in salt water.
Can you iron a molded zipper?
With care. Manufacturer sources cite a 130 °C limit and advise placing a cloth on top.
Are molded zippers lighter than metal?
Yes, at the same size they are lighter than metal.
