Copyright RetroZone inc.2020



SDSR Super Duty Spring Return Series
commercial grade dampers
starting at $
With Free Domestic Shipping
Available in 24vac and 110vac

when you have had enough of cheap, 2 wire spring return dampers! 



Available in 24volts or 110 volts, with or without end switches. 

Had enough of  residential grade spring return motor and damper failures? Move up to the commercial  grade Belimo TF Series  2 wire Spring return dampers. Service calls are expensive, only to find a cheap spring return damper at the source of your problems! 

The Super Duty Series of Spring Return Dampers use the industry renowned Belimo TF series spring return motors, mounted on our commercial grade Steel Can with Duro Dyne Drive hardware-Best in the Business.

1/2  the power, but twice the torque! How is that possible? Unlike cheap direct drive spring return motors, the Swiss engineered  Belimo TF series is a “gear train” motor, and uses a gear train to multiply torque from a smaller, more efficient motor.  And that's important, since a spring return motor pulls power continuously to overcome the spring, when energized. 

*Works with any 24vac  zone control  system , replaces any two wire spring return damper.

*Available in 24 or 110 volts, optional end switches (call factory) 

* 5 year factory warranty on the Belimo TF series motor.  

*Field reversible from Normally open to Normally closed

*All Duro Dyne commercial grade damper drive hardware

*Uses half the power of cheaper residential grade spring return dampers

*Higher Airflow Capabilities 

*Muscular 22 inch pounds of torque at 5va, 2.5 watts

*Handles larger ducts with ease.

*Low leakage Blade Seals, no plastic parts to break!

*Blades are bolted, not spot welded, in place. 

For Duct sizes 12 inches and up,  The Super Duty Spring Return is a must!  larger round ducts carry far more airflow, and many residential grade spring return 2 wire dampers  are just not up to the task-Blades can “flutter” in the air stream, and overall stresses on the springs and other parts-especially plastic parts-can lead to early failure. 

There is no finer. better built spring return damper on the market, at any price.  No Plastic parts, spot welds, or external springs to break.  And all backed by Retrozone, where dampers and zoning is our only business!


Due to the low sales volume on these 3” and 4” sheet-metal dampers, a slightly different damper can may be used than the one pictured. This damper will still feature a Belimo LMB24 motor.



SDSR-03 ($174.35) 
SDSR-04 ($174.35)
SDSR-05 ($146.95)
SDSR-06 ($144.95)
SDSR-07 ($150.95)
SDSR-08 ($150.95)
SDSR-09 ($154.95) 
SDSR-10 ($154.95)
SDSR-12 ($162.95)
SDSR-14 ($168.95)
SDSR-16 ($177.95)
SDSR-18 ($194.95)
SDSR 3",4",5",6",7",8", and 9"

SDSR 10", and 12"

SDSR 14", and 16"

SDSR 18"




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