DESC: Usher fresh outdoor air into your home without bringing in the cold, dampness, dust and pollen with this Bionaire Window-Mounted Air Cleaner. This sleek window unit mounts easily with the included window mounting kit in double-hung windows from 26" to 38" wide. And its slim design won't obstruct your window view. Once you've got it installed, this super system gives you the choice of three motor speed settings that pull fresh air into your home from outside. But you won't feel the chill of autumn winds, rainy days or even icy winter mornings because the heat balance system automatically equalizes the temperature of the incoming air to that of inside air. You get all the fresh air you want without any of the discomfort of outside conditions. Your air cleaner even lets you know when it needs cleaning and maintenance with its "service" warning message, so keeping it in perfect working is a breeze.