What if you could easily save $200 or more on the cost of heating your home each year? Well you can. Itís as simple as sealing off your ceiling AC vents with special covers that are designed to prevent heat loss, conserve energy, and save you money! Covering central air-conditioning vents prevents icy drafts from entering your room through open vents. Closing the louvers in your grilles won't stop airflow and associated heat loss because it,s not a total seal. Hot air produced by heating systems in fall/winter lose thermal values of 30% or more through the central air duct system. Heated air rises, and is drawn through unsealed central air conditioning vents into ductwork in the cold attic. The air is re-introduced as icy drafts through lower vents. A 15 to 20 degree difference often exists between upper heated room air and lower register re-cycled cold air, emitted from lower air ducts. Covering standard thru-the-wall air conditioners, window AC units and attic fan vents is also equally helpful. The covers are very affordable and install in minutes.