I found this and thought I'd share. Add the "h" to the prefix.
In the instructions he has a link to a video he made, for those interested in making one. Personally, I'd modify it slightly so that it would only take a smaller square of N95 mask for a filter element. In the video he shows folding up a whole N95 for the filter.
I personally have a beard that's a few inches shy of reaching my belly button, so masks are a moot point at this stage of the game. I'm also pretty rural and not concerned with daily mask wearing, but this might come in handy for those of you in more population dense areas.
ttps://drive.google.com/file/d/1j8nZUFOTE4rF_nAn-R7qPiUd8B1jo47n/view