3M Altitude Mask Caps

WARNING: USE AT YOUR OWN RISK 
[Consult with your physician before attempting use of a respiratory restriction device]

Since I already owned a 3M Half Facepiece Respirator, and didn't want to spend another $100 on a dedicated “altitude mask” (if you're looking at this, you likely know the ones I'm talking about) so I designed a cap to block off one side's inlet, and then designed progressively smaller inlets for the other side. Once it seems as though you're able to perform at a normal level with one inlet, install the next size down, and repeat!

The benefit of using this system over something that might restrict the exhale also, is breathing deep at altitude is really a matter of being able to suck in enough oxygen, there's no restriction of the atmosphere on your exhale.

(So far I found the 14mm inlet to be too “open” to be an effective stimulus, so I've started my training at the 12mm.)

Compatibility: The design is based off the 3M “6000 series” masks with the bayonet-style mount. So it should fit and work with all half and full face respirators that use this mounting system for their filters.

I ended up printing mine in PLA Plus, and so far they've been holding up just fine. Would like to later try in PETG perhaps for additional durability.

Printed at 0.12mm, with 25% gyroid infill. Raft was required for me on my Ender V3 SE.