The Replacement Carbon Pre/Post Filters are designed for Holmes air purifiers that use Part AOR31. Each filter measures 4-1/4 inches by 9-1/2 inches by 1/4 inch and is packaged as a six pack for multiple replacements. These carbon filters work as both pre and post filtration to reduce odors and improve overall air quality. They are engineered to be a direct fit with compatible Holmes units and are built to meet or exceed OEM performance standards. Regular replacement ensures optimal filtration efficiency and continued clean air in your space.
