The Best Window Fan.

This window fan produced 22% greater air velocity yet was the quietest, thereby earning The Best rating from the Hammacher Schlemmer Institute. Analysts' anemometer readings showed The Best Window Fan produced 533.5 feet-per-minute winds, far superior to the second place model that mustered only 439 fpm. The highly efficient, quiet unit produced only 0.19 dB for every foot-per-minute of air velocity, unlike a competing fan that generated 0.37 dB and nearly twice as much noise. The Best model's dual fans are reversible and operate independently, allowing one fan to draw air inside while the other pushes air outside for optimal circulation. The unit has a digital thermostat and its accordion side panels adjust from 24" to 40" wide to fit nearly any double-hung or slider window.