Bemis by Aircare Wicks filter out mineral deposits and wick moisture continuously. They have a comparatively large amount of paper in them, capable of providing high output and long life. In most areas, they will last the entire humidifying season. All these differences in paper wicking ability, amount of paper per area volume, and wick construction increase performance and lengthen the life of the wick. Fits 800 series. Measures 12"L x 11"W x 4"H.While air cleaners may reduce particles and allergens in the air, allergic symptoms are caused by a variety of sources. Therefore, this product is not meant to treat or mitigate any medical condition. Please consult your physician.