Our KN95 Face Mask is KN95 and European FFP2 certified, similar to the American N95 certified mask. KN95 is an industrial manufacturing standard meaning our masks are effective against 95 percent of particles with a mass median diameter of 0.3 micrometers or larger. Properly worn masks can protect very well against PM10, PM2.5, and smaller particles. BFE>95% (Bacterial filtration efficiency) Specifications: Disposable Face Mask Elastic Ear-Loops 95% Filtration Made In China Due to the nature of this product there are no refunds/exchanges or price protection .