Features & Benefits: The innovative and patented Positive Facial Lock® (PFL®) feature utilizes our exclusive Twist-Seal® technology that allows the user to create a custom fit each and every time. This unique feature significantly reduces the possibility of the user inhaling airborne contaminants and creates a positive seal to a variety of facial sizes and features. Additionally, the integrated Magic Arch® prevents the mask from coming in contact with the user’s nose and mouth thereby making it easier to breathe while enhancing filtration efficiency. The hypoallergenic, fluid resistant materials used in the PFL masks create a durable exterior and a soft, comfortable interior.