I am selling a mask used for treating sleep apnea. It is size M. This type covers both the nose and mouth, making it ideal for those who tend to open their mouths during sleep. The cheek side has a hook design for easy removal and attachment. Please consider purchasing. Please see the photos for the condition. It is in very good condition and can be used immediately upon arrival. This is a used item, so please check the photos before purchasing. #FisherAndPaykel #fisher #pykel