Fits Emerson humidifier models HD1100, HD1102, HD1200, HD12001, HD1202, HD1204, HD1212, HD1214, HD12040, HD12041, HD1300, HD1301, HD13000, HD13002, HD1303, HD13003, HD1300W, HD13030, HD1305, HD13050, HD1405, HD1406, HD14060 HD14070, and HD230. * 4 filters per box. * Measures approximately 6 1/2" x 9" x 2 1/2". * Patented rigid support long-lasting design. * For optimum performance, replace filter twice a season.