Q-Max? Pro Series Fans are a quiet line of fans that feature the familiar Max-Fan? and Max-Fan? Pro Series motors integrated with an acoustic foam liner in a muffler for maximum sound absorption. Unlike using most aftermarket mufflers, this integrated design muffles both the fan's intake and exhaust while also encapsulating the motor results in unrivaled airflow and whisper quiet operation. Q-Max? fans also utilize built-in hang tabs for additional isolation and easy installation. Some models include a built-in 3 speed selector.