The 00-100-03 is ATM's most powerful and flexible air moving system, the System 1 is available in two versions. The in-line version is suitable for indoor use, while the EXT version is mounted in a weatherproof enclosure, suitable for outdoor use in virtually any climate. Both can move over 100 CFM while producing very little noise, thanks to a precision-balanced rotor. The in-line version is now Energy Star rated; airflow has been increased by 40% to 140 CFM, power consumption has been reduced while noise level remains the same.