Sunbeam SWF3000 Twin Window Fan with Thermostat Slim twin window fan fits most double-hung and slider windows Manually reversible for air intake or exhaust; 2 speed settings Comfort control thermostat; simple dial controls; quiet operation Adjustable extender screen and bonus extender panel included Measures 23 by 4-1/8 by 10-5/8 inches; 1-year limited warranty