HVAC Premium8" Butterfly Damper - Control Your Airflow on Drop Ceiling grilles of 24x24 (8" Round Duct Opening)

This construction/finish of the damper is pretty fair quality for the price. Easy to install and adjust once it is in place. It does a good job of holding back the airflow where it's not needed. Occasionally they whistle when they are fully closed, but I think that has more to do with the fact that not all diffuser collars are perfectly round or the same size and some air gets through. I'd give this my recommendation.

I needed this product to block out air flow coming through a ceiling register. The damper is somewhat effective. It helped to redirect air, but there was still a large amount of cold air coming through the vent. I'm certainly not an HVAC expert, but I feel that it was installed correctly. The product has definitely improved the airflow issue, but I wish it could block out even more air.

Product arrived promptly, we’ll packaged. It was simple to install and took longer to move the ladder than it did to install the units (we bought 8). They definitely help balance out the AC between offices. Before we had them, the front office would be too warm and the back offices would be so cold we were running space heaters.

We have several registers that were to powerful and the people in the offices where the registers are located were either to cold or to hot. Took about 10 minutes to install damper and now everybody is happy

This butterfly damper is a near identical replacement for what we had existing. The mounting tabs differed slightly but nothing a few self taping screws couldn’t fix. Installed in a few minutes. The key is plastic and will strip easy so this is better served for a vent that isn’t adjusted too often. Perfect for us as I only anticipate us adjusting initially and probably never again. Great buy!!

Work and fit just as they should. Not sure why people say the plastic handle breaks. No need to wrench on it. I would recommend that you spray it with some PTFE lube or lithium grease.

The control key (white plastc) needed to be six inches longer for my needs, in fact a longer length would allow trimming as the key wears. Immediately after install the two wings do not move the same number of degrees, slippage I guess. Its got problems, but it does contol air flow

This solved a very specific problem in our office. The install was simple and you can control the airflow with simple adjustments. The office is more comfortable now. Especially for the people sitting directly under the vent!

Fits perfectly onto the 24 x 24 suspended heating vent and is adjustable. Little stiff. Needs a little lube prior to installation.