Fantech Inline fans don't have sone ratings (a measure of loudness), but that doesn't mean you'll hear them. This fan consists of two components. The small grill housing that is installed at the ceiling, and the fan that is installed in a remote location well away from the bathroom. Because the fan is not right at the ceiling, the motor noise won't be as loud, and the penetration through the ceiling will be smaller than with a conventional bathroom exhaust fan. This fan should be installed with at least 8 feet of insulated flex duct between the grill and the fan. Flex duct will not only help reduce the transmission of sound from the remote fan back to the bathroom, but it is often easier to install than rigid duct. Two models are available. The PB-110 is a 110 cfm fan, comes with a 6 inch square grill housing with damper, and is designed for use with 4 inch flex duct. The PB-190 is a 190 cfm fan, comes with a 8 inch square grill housing with damper, and is designed for use with 6 inch flex duct. Both are rated for use in wet locations. * Electrical Specifications (PB-110): 120 volts AC, 60 Hz, 20 watts * Electrical Specifications (PB-190): 120 volts AC, 60 Hz, 67 watts * Maximum Airflow (PB-110): 110 cfm (for bathrooms up to 800 cu. ft.) * Maximum Airflow (PB-190): 190 cfm (for bathrooms up to 1,520 cu. ft.) * Grill Size: 7 inch diameter * Grill Housing (PB-110): 5.25 inches deep x 6 inches square * Grill Housing (PB-190): 7.2 inches deep x 8 inches square * Certifications: UL, CUL, HVI * Manufacturer Warranty: 5 years * Origin: Germany