Xiaomi Mi Smart Air Purifier 4 Pro -EN has a Particle CADR of up to 500m³/h* and can release 8330L* of clean air per minute. The Xiaomi Smart Air Purifier 4 Pro utilizes a high-efficiency filter with a large area and high-quality activated carbon with a large volume. The filter lasts for 6-12 months. There is no necessity to replace it often. The purified air can get to every corner of your house, so you and your family can breathe healthily all the time.