This Electric Fan Intelligent Mask has a filter element that possesses the same effect as the KN95 and N95 masks. It is powered by a small electric fan that makes breathing easy. The mask is rechargeable and can be used for a long time. With 4 replaceable masks, you can just replace them after using them. The best thing about this product is that the use time of the filter element reaches 1 month at most, allowing you to use the 4 extra filters for 4 months. This mask functions as an anti-fog, anti-formaldehyde, anti-second-hand smoke, and anti-bacterial.