These masks are intended to be used for protection against solid and liquid aerosols in wood, cement, glass working, textile, mining and construction environments. They are extremely durable and they have a soft and comfortable inner surface with an adjustable nose piece and secure head straps for a proper fit. There is a low breathing resistance for increased worker comfort. All FFP3 masks are to be used in situations up to 20 times the Occupational Exposure Level (OEL). Exhalation valve reduces breathing resistance.