Panasonic WhisperFit Retrofit Ceiling Mount Bathroom Exhaust Fan, 50-80-110 CFM, FV-0511VF1WhisperFit DC Fan features a built in energy efficient ECM (DC) motor with Pick A Flow airflow selector that allows you to select required airflow (50, 80, or 110 CFM). Single hinged Flex Z Fast bracket, pre installed alignment guides, and temporary clip allow for flexible, fast, and easy installation. This vent fan enables you to utilize existing duct, while its low profile housing design ensures a proper fit in any bathroom ceiling or other areas of