The Extreme Series offers 3-speed fans to truly put full control in your hands. With the system set in the Low setting, you can maintain a 55°F cellar at an ultra quiet 51 decibels for the 3500ti and 5000ti, or 57 decibels for the 8000ti. This fully featured line also includes WhisperKOOL’s most advanced controller to keep all of the cellar vitals in check. Utilizing a series of monitoring probes inside the unit, the controller is able to ensure efficient high performance and long cooling unit life. Acceptable for mounting through exterior walls and can operate in a 110°F exhaust environments. Maintain 55°F and 50-70% relative humidity in a cellars up to 800cu. Ft. (3500ti), 1250 cu. Ft. (5000ti),or 2000 cu. Ft. (8000ti) in size.