The Sharper Image Portal Window Fan (SIPORTALWHT) is a cutting edge product designed to provide superior airflow and convenient controls. With its strong airflow, this fan can efficiently pull fresh air in from outside or exhaust stale air out of your home. The reversible exhaust feature allows you to easily transition the airflow from fan to exhaust mode at the touch of a button. One of the standout features of the Portal Window Fan is its perfect fit design. It can seamlessly fit into windows ranging from 24 to 38 inches wide using an innovative modular block system. This fan is suitable for use in both single-hung and double-hung windows, as long as there is an opening at least 8 inches tall. Controlling the fan is a breeze with its intuitive controls. You can choose from three speed settings to customize your comfort level, and the noise level is minimal even at the maximum setting. The fan operates quietly with a maximum noise level of 52.6 dB and a minimum noise level of 40.2 dB. The Portal Window Fan is backed by Sharper Image’s commitment to superior support. Please note that the fan has product dimensions of 6.58 inches tall, 23.85 inches wide, and 6.12 inches deep. Depending on the depth of your window, you may need to remove the window screen for installation. The fan can only be installed in a horizontal position and is built to meet U.S. voltage requirements. It is certified, safety-tested, and warrantied for use only in the U.S.