Fresh air ventilation control panel, 14" round 2-position damper, 120/24 20VA transformer. Manual Balancing Damper 16 x 16 with locking quad The control panel is available separately (iO-FAVPAN) and can be ordered with additional size dampers both round and/or rectangular. The iO-FAV has single adjustment setup, exhaust fan control option, outdoor temperature and/or humidity limit option and damper override capabilities. The iO-FAV fresh air ventilation system is designed to introduce fresh air into a building through an intake damper controlled by a micro-processor logic panel.