Review (3/5): Heat from breath makes it too uncomfortable to wear
The concept of this product is great but I think it needs to have larger spaces to allow the air that we exhale escape the cup. It is quite uncomfortable in my opinion to be wearing a mask in the first place but to then have this plastic cup holding in a lot of the hot air I exhale before it can escape out of the mask is terrible.
My mask fits really well and doesn't allow much air to escape in the first place but because of the fabric against my face, it is not a problem. But this cup just won't cut it for me. It might work fine for a looser mask that doesn't have a nose wire or if you live someplace that is always cold, but this insert in Hawaii in the summertime is just too uncomfortable.