Generic K-N95 Polypropylene Disposable Face Mask Features A Cool Flow Exhalation Valve To Prevent Passage Of Microorganisms, Body Fluids And Particulate Material Into The Airways From Nose And Mouth To Help You Breathe Easier And Stay Germ-Free In Various Indoor And Outdoor Places. Its Stretchable Earloop Straps Can Be Adjusted To Meet The Most Head Sizes While Assurance That It Won'T Hurt Your Ears Or Nose During Extended Hours Of Wearing.