Recommended annual replacement for homes without smokers and more often for homes with smokers. Please choose from the models below for the corect Media Filter for your Space Gard Air Cleaner. Aprilaire Air Cleaner Media Filters Bemis Air Purifier Filters Schill's, llc 103 Curtis Street Arlington, WI 53911 Limited Hours Customer Service: 888-528-0225 Email: Info@Schills-Humidifier.com Fax: 608-592-3205 Manufacturer's Numbers: Aprilaire: 800-334-6011 Broan Fan/Heater Questions: 800-637-1453 Delta Faucet Questions: 800-345-3358 Grohe Faucet Questions: 630-582-7711 Hart & Cooley Questions: 616-656-8200 Kohler Faucet Questions: 800-456-4537 Moen Faucet Questions: 800-289-6636 Stiebel-Eltron: 800-582-8423