These fans come complete with a movable-blade louver. The louvers are gravity operated so they open only when air flows through them, which prevents backdrafts.

Belt-drive fans are quieter and have a longer life span than direct-drive fans because components can be replaced if worn or damaged.

Direct-drive fans have fewer moving parts than belt-drive fans for less maintenance. Use these fans to draw stagnant and humid air out of a room or area.

Better suited for dirty, dusty, and damp environments than standard belt-drive fans, these have a totally enclosed motor enclosure.