Larger surface area means more air flows in and out of the mask -- without a valve Durable Dura-Mesh shell prevents collapsing from heat and humidity FlexFit design fits the contours of the face and mouth for comfortable extended-wear Soft foam nose...
Larger surface area means more air flows in and out of the mask -- without a valve Durable Dura-Mesh shell prevents collapsing from heat and humidity FlexFit design fits the contours of the face and mouth for comfortable extended-wear Soft foam nose...