Keep your indoor air quality at its best with the Protec WF813 Extended Life Humidifier Replacement Filter. This filter is designed to fit the Kaz humidifier model WF813 and is made of durable plastic material. With a coverage of up to 110 sq ft, it is perfect for any room, especially the bedroom. The filter operates with electrical power and uses cool mist humidification method with one speed. It is easy to install and weighs only 1 lb. The replacement filter is compatible with medium-sized rooms and can be used for a longer time. Get your hands on this NOS item to ensure the best air quality at your place. Two different types of boxes.