GOGOGlobal Upgraded Blue Mesh Treated Layer Humidifier Wicking Filters Compatible with Honeywell HAC-504AW, Filter A for Models HAC-504, HAC-504AW, HCM 350 and Other Cool Mist Models (4 Pack)

Lxiyu Upgraded Humidifier Wicking Filters Replacement Compatible with Honeywell HAC-504AW, Filter A for Models HAC-504, HAC-504AW, HCM 350 and Other Cool Mist Models (4 Pack)

Protec Humidifier Tank Cleaner, 1 Count - Colors May Vary

ProTec PC-2 Humidifier Tank Cleaning Cartridge, 2-Count Packages (1 pack of 2 cartridges)