Fits Moosoo K12 K12 Pro K13 Cordless Vacuum Cleaner. Made of high quality materials that block dirt, sawdust, dust, wood chips, pet dander and other particles as small as 0.3 microns, reducing dust and other allergens in the air you breathe. As part of normal maintenance, installation is simple: just remove the dust container, twist the old filter and remove it to replace it with a new replacement filter. Washable and reusable K12 filter. It is recommended to replace the vacuum cleaner every 2-3 months to ensure optimal performance. Package Content: 4 filters. Your satisfaction is our goal! Note: The data is all measured manually. Due to the difference in light and display, please allow an error of 1-3 cm. Please refer to the actual item you received.