Features: Easy to install: This replacement filter is specially designed for second generation USB air coolers, without any special tools, it only takes about 2 minutes to complete, giving you a cool and brand new cooler. High-quality quality: No need but your air cooler does not work, you only need to replace a filter element and you can use it again, allowing you to breathe fresh and healthy wind and protect the health of your family. Function: It can effectively block impurities, dust, etc. in the air, improve the quality, and keep the air cooler clean. Replacement frequency: It is recommended that the filter be replaced every 2-3 months to avoid excessive use of product bacterium. The replacement filter is suitable for mini portable USB air purifiers, which can be absorbed quickly and effectively. Package Includes: 1x Air Cooler Filter Specifications: Material: Plastic+Non-woven Fabric Weight: 200g Size: 12.8x10.5cm/5.03x4.13inch note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.