NATO40, GP5, what's it all mean?

NATO40 VS GP5 System

NATO40 is a universal gasmask standard. NATO40 screw fixtures measure 40mm in diameter.  However, KB3D also has a 'GP5 System'.


What's the point?

Well, the NATO40 fitting is quite narrow, which leaves attachments structurally vulnerable.  We wanted to design products that can take a lot of punishment - for instance, the Vac-u-lock gas mask attachment.  You don't want to be riding a sub's face and for the attachment to snap off of the gas mask as you start to reach climax!  So, we designed the GP5 System.  This replaces the metal valve on a GP5 gas mask, which is significantly wider in diameter than a NATO40 screw.  Greater diameter = more structurally sound = products can withstand more abuse.

Will using the GP5 System break my gas mask?

This system requires you to remove the metal valve unit from a GP5 Russian gas mask, and replaces it with our GP5 system.  However, the modification is reversible. Provided that you used appropriate care when replacing the metal valve unit, you should be able to remove our GP5 system and reinsert the metal valve unit.  However, we won't be held responsible if you were heavy handed and broke your gas mask.  If you're not confident in replacing it, just keep in mind that this type of gas mask is one of the cheapest on the market.

If I replace the metal valve, does that mean I won't be able to use NATO40 attachments?

Not at all.  This opens doors, but doesn't shut others.  Now that you've replaced the metal valve with our GP5 system, you can quickly screw in bulkier attachments.  However, if you want to use a NATO40 attachment, we have have a GP5-NATO40 converter.  It's a simple screw, that makes the GP5 system, NATO40 compatible.  This system is simply a screw thread which allows the quick exchange of multiple attachments without any faff.  Perfect for you rebreather fans out there.

I like the sound of the GP5 system, but I'm only interested in the Vac-U-Lock and Funnel - do I have to pay for the GP5-NATO40 insert, if I'm not going to use it?

No.  We sell the two items separately, so you don't pay for something that you're not going to use.

What can I use with GP5 that I can't use with NATO40 and vice versa?

The table below shows which attachment works with which system.


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