We've got you covered with the Pack of Reusable Valve Face Covers With PM2.5 Filters  Comes in a pack of 3, 6 or 9 face covers with refills of PM2.5 filters Made from comfortable sponge materials with stretchy ear loops Complete with an air valve on the side Washable design can be reused up to 8 times Dimensions: 30cm x 13cm   Buying Options: 6.99 pounds instead of 69.99 pounds for the 3-Pack of Mask (With 6 Filters) - save 90% 9.99 pounds instead of 79.99 pounds for the 6-Pack of Mask (With 12 Filters) - save 88% 12.99 pounds instead of 89.99 pounds for the 12-Pack of Mask (With 18 Filters) - save 86%