WhisperCeiling 110 CFM Ceiling Mounted Fan: * The Panasonic WhisperCeiling Bathroom 110 CFM Fan, APPA11VQ5 features a quiet operation at .25" water gauge * Continuous, trouble-free operation for many years * User-friendly installation * The <0.3 sone Panasonic bathroom fa offers a built-in damper to prevent backdraft * Power consumption (watts): 21.1 at 110 CFM and 20.7 at 91 CFM * Energy efficiency (CFM"s/watts): 5.3 at 110 CFM and 4.5 at 91 CFM * Speed (RPM): 950 at 110 CFM and 1161 at 91 CFM * Duct diameter: 4" * Mounting opening: 10-1/2 sq in * Grille size: 13 sq in * Bathroom Ceiling Fan Dimensions: 10.83"H x 14.17"W x 16.73"D * Bathroom Ceiling Fan Weight: 10.36 lbs