Filter for fountain Petwant W3 - Accessories - Electric-Collars.com
Geovent - W3 - Filters - Mobile Filter Unit by Vent-Tech Ltd.
Whirlpool® G9IXEFMWS00 Compatible Refrigerator Water Filters (made by American Filter CompanyTM Model number AFC-RF-W3) Made in U.S.A – American Filter Company