Shopper What's the difference between regular and medium?
MARK S You have to have an exceptionally wide face for the regular-sized mask to fit properly without leaking. I have a large head and broad face and the smaller medium-sized fits me perfectly. The regular is just too big for me.
RICHARD K I have tried both the Regular and the Medium in this mask. Medium is supposed to be for people with smaller/thinner faces. My wife and I have what you would consider regular sized faces, but the Regular leaked on us both. We both own the Medium and have had no problems.