Good for those of you who are blind as a bat (oh wait that me)
A bit different from what I was expecting, but still works well with the mask and good for what it is. If you were expecting to be able to drop your own eyeglasses straight in though, you may be let down. I haven't taken the whole thing apart yet for fear of forcefully disassembling something that was not meant to be disassembled, but the setup is surprisingly nice and accomodating for different face shapes and sizes.
Obviously, the frames need to have a set of your own prescription lenses fitted and installed to them.
It should go without saying that if you need vision correction and plan to use your gas mask as more than a cosplay or "special fun time enhancement" piece, you should definitely get these functional ASAP and stop just donning it over your regular eyeglasses, dummy ❤️