Holmes 9 Twin-Blade Digital Window Fan makes cooling your home a breeze. This dual blade fan is conveniently designed to fit most double-hung and slider windows and includes 2 built-in expandable extender panels for a custom fit as needed from 23.5 to 35.5 . The electronically reversible airflow blades can bring fresh air inside exhaust hot air out or exchange both simultaneously. It features 3 speed settings low medium and high to adjust your airflow and a high-speed 14.4 ft./sec. velocity. For added convenience it includes 2 sturdy feet to allow for tabletop or floor use outside of the window frame. Designed to keep a cool breeze in any room it works great in living rooms kitchens bedrooms and home offices. Features a remote control white finish 3-year limited warranty and is ETL certified.