Air Vents for Crawl Space

If surrounding air contains more moisture than the lumber used in the construction of your home's foundation, moisture migrates into that wood, and that's not a good thing. This powered crawlspace vent has a quiet electric fan that moves that humid air outside through your existing vent, to help gradually dry out the space. Set your desired "fan-on" humidity level right on the sensor (instructions included); since it won't be needed at temperatures below 40° F, an automatic thermostat shuts the fan off. Mounts behind your existing vent, so it can't be seen from outside. Ventilates up to 1650 cu. ft. Measures 9"x19"x3" thick, and fits an opening 8"x16". Hardware included. Grounded 12" cord. UL listed.