3M HALF FACEPIECE REUSABLE RESPIRATOR PROFESSIONAL MEDIUM This respirator is comfortable,durable and easy to use. With a faceseal of an advanced liquid silicone material providing a softer feel on the face, a unique head suspension to reduce tension and pressure points and the 3M Cool Flow Exhalation Valve for reduced breathing resistance, The Professional Series is the most comfortable respirator available. Convertible from a conventional style suspension to a drop-down mode in one simple adjustment makes it a versatile choice.