"Comfortable Ears with Long Time Wear SOOMLAB AIR ON MASK KF94" Certified by the Ministry of Food and Drug Safety "From KF94 certification to FDA registration! SOOMLAB AIR ON MASK KF94 is a safe mask you can trust." "As an index certified by the Ministry of Food and Drug Safety that indicates the performance of blocking particles, the higher the KF index, the higher the blocking rate of small particles. SOOMLAB AIR ON MASK KF94 is classified as KF94, and blocks 94% of the fine dust particles that are on average 0.6ã?? in size." "The enhanced four-layer structure and MB static filter blocks not only droplets but also particulate harmful ingredients such as fine dust and yellow dust." Inner layer: non-irritant inner layer that uses thermal bond (EXCELLENT grade on the German derma test)