Bionaire humidifier wick replacement filters with antimicrobial agent! * Fits Bionaire humidifier models BCM7510. * Measures approximately 4" H x 4 1/2" ID x 6 1/2" OD x 1" Thick. * Honeycomb filtration to trap mineral pollutants found in water and help prevent them from entering your home. * For optimum performance, replace filter at the beginning of each season or every 2 months depending on use.