Compatibility: Compatible with replacement Holmes C carbon pre-filter (HAPF60CS). Model Compatibility: Fits Holmes air purifiers models: HAP8765, HAP8615, HAP8650B-U, HAP759-TU, HAP9726B-U, HAP9726-U, HAP726-U, HAP756-U, HAP633-U, HAP616B-TU, HAP616-TU. Fits Bionaire model air purifiers: BAP260, BAP520, BAP615, BAP625, BAP650, BAP815, BAP825, BAP1125, BAP1150, BAP1175, BAP1225, BAP1250, BAP1300, BAP1412, BAP9200, BAP9700, CBAP520. Also fits GE Models: 106633, 106643, 106653, 106569, 106853. Air Quality Improvement: Activated carbon reduces household odors from cooking, cleaning and pets. Also captures large particles before reaching the filter and extends its life. Maintenance: Recommended to change every three (3) months under normal conditions, and more often under harsh air conditions. Multipack: Each package contains four (4) replacement filters. Replacement Filters, 4 Pack – Compatible with Holmes HAPF60CS (C Pre-Filter) for Holmes Air Purifier Models HAP8650B-U, HAP759-TU, HAP9726B-U, HAP9726-U, HAP726-U