With 3 packets per box, the AIR-O-SWISS Demineralization Cartridge Refill 7533 is more economical than disposing and replacing the entire demineralization cartridge. You can keep your existing demineralization cartridge and simply refill the cartridge for a savings of over 45%.

Refill Resin Granules 3pk for AIR-O-SWISS Humidifiers:
7131 (AOS 7131), 7133 (AOS 7133), 7135 (AOS 7135), 7142 (AOS U7142), 7144 (AOS 7144), 7145 (AOS 7145), 7147 (AOS 7147), U200 (AOS U200), U600 (AOS U600), U650 (AOS U650).

Contains 3 (three) 3.88 oz packs of resin granules.

• More economical than replacing entire demineralization cartridge - three uses per box
• New and improved: Styrofoam plug and refill cup makes for much easier and cleaner refills.
• Refillable packs of resin granules for use in Air-O-Swiss Demineralization Cartridge
• Removes minerals from the water to reduce or eliminate "white dust"

Use one refill pack every 2-3 months. Each box provides for 6-9 months of use.
The resin granules in these packs are used to refill the Air-O-Swiss demineralization cartridge, which helps reduce white dust. White dust is a deposit of minerals left behind from the water in your humidifier. The cartridge should be refilled every 2-3 months, however the cartridge may need to be refilled more often depending on water hardness and how often the unit is used. An indication of when the cartridge needs to be refilled can be White dust around the humidifier, or reduced amount of mist output. If white residue still forms around the humidifier after the cartridge has been refilled, please make sure that the water you are using is untreated (do not use with water softeners or ion exchangers).

Refill Instructions for AIR-O-SWISS Demineralization Cartridge AOS 7531 [PDF]