The Mclean Engineering 2NB424D56P 29-4121-00 REV 2 is a Pentair APW McLean centrifugal blower designed for HVAC and refrigeration systems. This corded electric blower operates on 115V power and has a 4-inch diameter, making it suitable for a variety of applications. With a sleek black color and a compact design of 13.5 inches in length, this model weighs 9 lbs and is an essential component for maintaining optimal airflow in commercial and industrial settings.