The for Smart Air Purifier 4 filter can capture retain the smallest particles in the air, as well as delay dust, pollen, pets tobacco smoke. The plastic base retains its shape original appearance for a long time. Three layers of efficient filtration to protect H13 Clean Class - Efficient cleaning of air pollutants in the air The adsorption of particles effectively removes formaldehyde It is recommended to replace the filter every 6 months Designed to filter PM2.5 particles, pollen . Filter your pet's wool dust High quality filters have a strong absorption rate, eliminating absorbing unpleasant odors gases such as volatile organic compounds Color: As shown Material: plastic Package Contents: 1 x filter Only the above package content, other products are not included. Note: Light reflection different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is and\/- 1-3cm.