3-Speed Airflow Output Designed for ultimate versatility, this Comfort Zone 9" Portable Twin Window Fan offers two speed functions that can generate a strong breeze or circulate the air in your home with ease. The output is controlled with the manual dial, allowing you to adjust the airflow by simply turning the switch. The twin fan design offers added power and helps fill your environment with fresh, cool air. The WT2 version has the all new quiet speed setting. Auto-Locking Expanders Equipped with auto-locking according expanders on the sides, this twin airflow window fan easily adjusts to fit the width of your window. These expanders are suitable for windows between 22-1/4" and 33" wide, providing a snug, secure fit. Manual Reversible Exhaust Function Not only can this twin blade window fan fill your home office, bedroom or living room with cool air, but it can also be reversed to push hot, stale air out from your home. This exhaust function is especially useful for combating hot, humid air. Simply adjust the exhaust or air intake function depending on your environment. Window Fan This Comfort Zone 9in. Reversible Twin Window Fan has a 3-in-1 design that allows you to choose from three different settings. The cooling setting brings in fresh air, while the exhaust setting removes stale air. Portable and Convenient Featuring a carrying handle, this twin speed window fan can be moved from room to room and window to window with ease. For added convenience, this fan also features two sturdy feet for tabletop use on your desk or bedside table.