Review (5/5): Works, with little help with Velco
They are not that thick, it does fit most mask and small hooks don't stay in place when removing mask. I had to put a small piece of Velcro on the center nose bridge. then I stuck the glue side of velco on the mask where it was comfortable to keep the " muzzle " from falling out when removing the mask. It does help you breath and talk clearer.