Looking for a replacement filter, have one of these Holmes humidifier models: HM7204, HM7305, HM7305RC, HM7306, HM6000, HM6000RC, HM6600, HM6005HD, HM729, HM4600, HM4600HD, HM630, HM7203, HM7405, HM7808, check out the HWF100UC3 filter. This filter replaces the original one just like new. You'll almost forget you ever changed it. Keeping up with filter maintenance ensures that your humidifier stays in good working condition.