With an aluminum housing, these fans stand up to corrosion better than the economy fans. They are direct-drive fans, which have fewer moving parts than belt-drive fans for less maintenance. All have a totally enclosed motor enclosure, which can be used in dirty,dusty, and damp environments.
Designed to spin freely with the slightest breeze, these fans create a vacuum that draws air out from buildings and ventilation systems—no electricity required. They are also known as turbine ventilators. Mount fans on your roof away from wind obstructions.