The R80TZD is a round, sealed, modulating/open/close, 3-wire zone damper that is used with a variety of controls to adjust the amount of airflow to a space.  Dual sealed for minimal leakage.
 
Compatible Controls
All zoning panels with Open, Close and Common damper terminals with external bypass.  
 
Specifications
Sealed - Foam gasket on peripheral of the blade. and a foam gasket attached to shell.
Damper Sizes - 6" to 20" diameters.
Damper Shell - Spiral wrapped 24 ga galvanized steel.
Damper Blade - 20 ga galvanized steel.
Mounting - Two screws. Molded glass filled ABS shaft and keyed to eliminate blade alignment.
Wiring - 3-Wire Connection.
Electrical Power - 24VAC or 24VDC. 2VA operating and 1VA holding.
Output Torque - 80 in-oz.
Operation Time - Fully opens or fully closes in approximately 3 seconds.
LED Indicators - Green LED indicates fully open. Red LED indicates fully closed.
Multiple Dampers - Up to 4 dampers can be daisy chained to define a zone.
Operating Temperature - -20 to 175 degrees F