2. Comfortable use: The blue pre-filter layer can completely filter, helping to maximize the life of the filter. High-quality filters captures mineral from hard water to stop white dust,improving the air quality of your home. Let your family live in a fresh indoor environment. 3. High-quality materials: The professional environmental protection imported blue filter paper has a diamond-shaped grid structure, which can ensure the maximum transmission of water and absorption of products. The ly upgraded blue grid appearance enhances product performance and further ensures the cleanliness of the product 4. Easy to install and replace-For performance, it is recommended to replace the filter every 1-2 months. Replace the filter regularly to make the air feel moist and warmer can help improve your breathing comfort, dry skin and sleeping. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.