Moisture-proof, breathable and low-resistance for breathing, nano-film masks have higher air permeability and moisture permeability due to their high pore uniform distribution and moisture-proof and moisture-permeable material characteristics, bringing users a more comfortable breathing experience. Adjustable wide flat ear straps, not tight ears, long-term wear of the ears, fit the face, enhance the user's comfort experience. There is a plastic nose clip, which fits the face and can be adjusted freely according to the size of the bridge of the nose, making the protection safer. The new nano-film protective mask is exquisitely crafted, with edge-covered wiring and well-proportioned stitches, which satisfy the functional use and pay more attention to details. Replaceable filter cotton insert bag: There is a replaceable filter cotton insert bag on the inside of the mask. If the filtration drops due to wrong washing method or excessive repeated use, you can use a replacement filter cotton. Washable and reusable. material: cotton size: one size