This Lochinvar component is a Flue Baffle, designed to increase the efficiency of heat transfer in heating systems. The baffle works by directing the flow of exhaust gases through the heat exchanger in a specific pattern, which allows more time for the heat to be absorbed into the system. It is made from durable materials that can withstand high temperatures and corrosive gases. This part is compatible with select models of Lochinvar's heating equipment and is intended for professional installation.