WhisperFit® DC Fan is an ideal retrofit solution. Built-in energy efficient ECM (DC) motor with Pick-A-Flow® airflow selector allows you to select required airflow (50, 80 or 110 CFM). Single-hinged Flex-Z Fast® bracket, pre-installed alignment guides, and temporary clip allows for flexible, fast and easy installation. Can be used to comply with the latest codes and standards. KEY FEATURES Revolutionary ECM motor with SmartFlow™ Technology ensures optimal CFM output Built-in Pick-A-Flow® airflow selector allows you to select your required airflow of 50, 80, or 110 CFM with a simple flip of a switch Single-hinged Flex-Z Fast® bracket provides flexible, fast and easy installation Low profile 5-5/8 housing depth fits in 2 x 6 joist size or larger Can be used to comply with ASHRAE 62.2, LEED, IAP and California Title 24