Perfect Replacement for Honeywell HAC-504, HAC-504AW & HAC-501V1 Filters Made from high-quality, durable material, these filters are compatible with the below Honeywell humidifier models: HCM-300 Series: HCM-300T, HCM-305T, HCM-310T, HCM-315T, HCM-350, HCM-350B, & HCM-450BCST HCM-500 Series: HCM-530, HCM-535, HCM-535-20, HCM-540, HCM-550, HCM-550-19, HCM-551, & HCM-560 HCM-600 Series: HCM-630, HCM-631, HCM-632, HCM-632TG, HCM-635, HCM-640BW, HCM-645, HCM-646, & HCM-650 HCM-700 Series: HCM-710 HCM-1000 Series: HCM-1000, HCM-1000C, & HCM-1010 HCM-2000 Series: HCM-2000C, HCM-2001, HCM-2002, HCM-2020, HCM-2050, HCM-2051, HCM2052, HEV-312, & HEV-355 Enviracaire Series: ECM-250i Package Contents 4 humidifier filters compatible with Honeywell HAC-504AW and HAC-504V1 Rest Assured with Durabasic's Manufacturer Lifetime Guarantee If you are ever unsatisfied with the performance of your humidifier filters, we'll refund your payment! Disclaimer: This is not a Honeywell OEM product. The Honeywell and Enviracaire brand names and logos are the registered trademarks of their respective owners. Any use of the Honeywell and Enviracaire brand names or model designations for this product are made solely for purposes of demonstrating compatibility. Packaging may vary, performance does not.