I have several medium Quattro frames to trade I and one one or two other tried once masks to trade.

I have bunches of 5 year old mirage Quattro masks and all the cushions have an M on the bottom of the cushion. So my question is, "does the M stand for medium"? Yes, I know this is a dumb question but I have recently been in the hospital mostly unconscious and three weeks in a coma. Now I am having ...