MSA Advantage 4000 Medium Size Twin Port Facepiece is made of silicone for added comfort. Facepiece includes bayonet adapters in lens, a net head harness and a nosecup. It is used in asbestos abatement, welding, sanding and grinding applications. It is compatible with air-purifying respirators, supplied-air respirators and powered air-purifying respirators. It is a one-mask system that can adapt to a wide range of respiratory applications.