This reusable face mask has up to 99% filtration, destroying viruses upon contact. It uses the latest nanofibre technology to offer between 99.7 - 99.9% filtration, deactivating respiratory viruses such as Coronavirus. The filtration is also two-way with sterilisation both inside and out of the mask, meaning both you and the people around you are protected. The lightweight RespiPro VK Face Mask is easy to breathe through and is reusable, offering up to 30 hours of protection. Because this mask offers both 99% filtration efficiency for pathogens and the ability to kill them, it is the ideal protective equipment for authorities, frontline staff, and the general public. The Large size is designed to fit average and large-sized adult faces .