The Maxxair Vent Maxxfan 4-Speed Powered Vent provides over 900 CFM to keep you cool and comfortable, removing hot musty air and odors. The fan can run with the lid closed to circulate air in the RV.• 12V DC, variable-speed fan• High-powered 4-speed exhaust only fan• Exhaust only• Opens and closes using a manual knob located at the ceiling• Easy to remove interior insect screen, no tools required• Twin lifting arms â no more lid fluttering in high winds or when driving• Powerful, fuse-protected, long-life, sealed ball bearing, 12-volt fan motor• 12" 10-blade fan• Flush-mounted, easy-to-clean keypad• Controls fan speed, thermostat, and exhaust functions• Closes securely for a 3-3/4" low-profile appearance• Smoke translucent lid• Fits all standard 14" x 14" roof openings Easy to remove interior insect screen Twin lifting arms so no more fluttering in high winds or when driving Flush-mount keypad controls fan speed, thermostat, & exhaust functions | Maxxair Vent 00B04401K Maxxfan 4-Speed Powered Vent, Smoke