REPLACEMENT HUMIDIFIER FILTER – The Filters Fast humidifier filter is the compatible replacement for Holmes HWF-64 humidifiers. REINFORCED DESIGN – The house humidifier filter features a reinforced design which makes the filter more durable and efficient. It’s recommended to change your filter every 2 months. COMPATIBLE WITH – Compatible replacement for Holmes: HM-1645, HM-1730, HM-1745, HM-1746, HM-1750, HM-2200, and HM-2220 (HWF-64). Compatible replacement for Hamilton Beach 05520, 05521 (05920) and more! EXTENDS THE LIFE OF YOUR FILTER – The Filters Fast humidifier wicking filter extends the lifespan of your filter in hard water areas by trapping minerals and sediments. DIMENSIONS – Size: 7.5x6.75 inch. Filters Fast compatible replacement wick humidifier filter meets the same quality standards as the name brand filters. Filters Fast Humidifier Filter Compatible Replacement for Holmes HWF-64 Filters Fast humidifier replacement filter meets the same standards as the name brand filters. The reinforced design makes the filter more efficient and traps minerals in your humidifier's water. Size: 7.5x6.75 inches. Compatible replacement for Holmes HWF-64 humidifiers. It’s recommended to change your filter every 2 months. These air cleaner filters are a compatible replacement for Holmes: HM-1645, HM-1730, HM-1745, HM-1746, HM-1750, HM-2200, and HM-2220 (HWF-64). Compatible replacement for Hamilton Beach 05520 and 05521 (05920). Compatible replacement for White Westinghouse WWHM-1645 (WWH-640). Compatible replacement for Sunbeam SCM-1746 and SCM-1747. Compatible replacement for Duracraft DH888 and DH890. Compatible replacement for Bionaire BCM-1745 (BWF-64).