iO HVAC Controls EB-3812 38 X 12 Heavy Duty Motorized Bypass DamperiO HVAC Controls EB 3812 ACTUATORS ARE INSTALLED ON 2ND DIMENSION 38 x 12 Heavy Duty Motorized Bypass Damper 38 x 12 Heavy Duty Motorized Bypass Damper, Static Pressure Controller monitors static pressure and opens the damper to relieve static pressure when it reached the set point on the pressure sensor. 5 YEAR WARRANTY Additional Information Item NumberEB 3812 BrandiO HVAC Controls