The FO-COVER-30 is a water-resistance cover, made from PU material for use with any 30” diameter PFO/WFO ventilation fan. With the simple zippered design, installation is quick and easy. Allows for protection against dust, debris and water intrusion when the fan is not in use. Works with any 30” PFO/WFO ventilation fan. Heavy-Duty PU construction for water-resistance Zipper design allows for quick and easy installation. UV Resistant Protects from dust, debris and water intrusion when fan is not in use.