QD Health IIR Surgical Face Mask Black 25 units are non-reusable, adult-size black surgical face masks that limit the spread of infection. They are single use, non-reusable. They have a life cycle of 4 hours and their filtering properties are reduced after this period of time. They are a Medical Device that limits the spread of contagion. They are Type IIR: resistant to splashes, such as blood or other biological liquids. One size, adult. Black colour. Contains 25 units.