Disposable for single use only. Lightweight 3 layer filter made of non-woven material. Close Fitting for comfortable wear. Size + Fittings 15 cm x 11 cm One box includes 50 pcs.  Disclaimer This product is not a medical device and is not a substitute of social distancing and practicing good hygiene, hand washing, and not touching your face. Smart Scholars makes no claims about the medical benefits of using this product.