ONE FILTER IS NOT SEALED - The Nispira C610 Filter Z Replacement is a 2 pack of HEPA-Type air purifier filters designed for the Winix C610 model. Made with carbon filter media and a plastic filter frame, these filters have a filter life of 6 months and are manufactured in China. The black filters have a diameter of 10 inches and a length and height of 9 inches, providing efficient filtration for indoor air quality improvement. Thanks for shopping our store!