Fits Bionaire models WH2510, WH3060, WS3510, WS3560, and WS3570. * Bionaire humidifier wick filters. * Measures approximately 7" x 7 3/8" x 2 1/2". * Honeycomb filtration to trap mineral pollutants found in water and help prevent them from entering your home. * For optimum performance, replace filters twice a season.