Pack of 4 Honeywell HAC-504 Humidifier Wick Filters. Aftermarket replacement filters manufactured by FilterBuy.;Designed by FilterBuy to fit Honeywell Cool Moisture Humidifier models 63-1508, ECM250i, DH835, HCM-53x, HCM-54x, HCM-300T, 310T, 315T, 330T, 350, 530, 535, 535-20, 540, 550-19, 550, 551, 560, 630, 631, 632, 632TG, 635, 640BW, 645, 646, 650, 710, HCM1000, HCM1000C, HCM1010, HCM1010C, HCM1020, HCM2000, HCM2000C, HCM2001, HCM2002, HCM2020, HCM2050, HCM2051, and HCM55019.;Compare to Honeywell Part # HAC-504AW. Dimensions: 5 H x 4 1/4 ID x 6 1/2 OD x 1 Thick.;Premium aftermarket replacement, designed by FilterBuy in the USA.;Humidifier FilterBuy: Breathe Better!