I have a two story home with a single zone furnace. My lower level (LL) would always be 5 to 10 degrees cooler than the upper level (UL). The LL is finished so no oppertunity to dual zone the HVAC system. I added a door seperating the two levels which helped but didn't solve the problem. I converted several of the LL vents to Flair 4x12 smart vents to see if the cocept worked. It did so now I'm converting the balance of the vents to Smart Vents. This 6x10 is the last to be converted. Works GREAT. Also, service is GREAT. I had problems with my Puck and after working with service, they replaced it under warrenty. Buying through the FLAIR URL you get 1 additional year of warrenty support and it works. This Smart Vent concept is the best way to handle the situation i'm in