I use this as a chin strap when using my C-Pap machine. It keeps my mouth shut, thus preventing air leakage. The chin strap provided with my machine always gave me jaw pain and a headache, but this product distributes the pressure more evenly and it causes no pain.
This is a great product, since I got it to help stop me from open mouth snoring. Works great and has the added bonus of lifting my face as I sleep. Very comfy.