I just bought a 4/3 NP Cortex chest zip neoprene and I am surprised to see that the model is equipped with a vulgar plastic zipper. Has anyone ever tested the strength of the mechanism? Why be so cheap on this detail for a product that is already in the mid / high-range of the brand?

Had plastic zips on all my wetsuits (number of different brands) wish I had them on other things like Board bags,

If you leave a wetsuit for a long time after sailing in salt water - and without rinsing it in fresh water - then you'll find salt corrosion on the zip.
That corrosion is then worse with metal zippers because it attacks the metal.
So some manufacturers use plastic zippers.

All zippers, if left for a while unrinsed, can jam with corrosion, and that's best cleaned with white vinegar or a coca cola soak.

I have several wetsuits, with various zippers, and have never had any problem - whereas with board bags and sail bags I have.
With board bags, I sometimes leave them for a year without use, and then I find I have a zip problem.

None of these issues happens if you can use or check your gear regularly.

How is the Cortex?
Is the chest-zip easy to slip-on and slip-off?

I have the Cortex 3/2 and the plastic zip is superb. No durability issues after a full year of reasonably intensive use

Thanks for your feedback. the fact that the zip does not strictly speaking seal the wetsuit, but just keeps the flap closed in this model, allow the manufacturer to cut some cost instead of using a zip type YKK?

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sakkai said..
Thanks for your feedback. the fact that the zip does not strictly speaking seal the wetsuit, but just keeps the flap closed in this model, allow the manufacturer to cut some cost instead of using a zip type YKK?

Have 3 O'neill Psycho wetsuits. Psycho is O'neill's highend line. All 3 suits have plastic zippers. Been using the suits for a couple of years now and have had no issues with the zippers.

Regarding sealing the wetsuit. It's called a wetsuit for a reason. The collars and zipper are supposed to let water get into the suit. The water forms a thin layer between your skin and the suit which helps insulate from either cold or heat. If you want to stay dry in your suit get a drysuit. Those have heavy duty zippers which keep the water out.

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sakkai said..
I just bought a 4/3 NP Cortex chest zip neoprene and I am surprised to see that the model is equipped with a vulgar plastic zipper.

can you tell us which wetsuits do not have plastic zippers? I think they all do. plastic is the best option unless you prefer corrosion and a jammed-up zip.