BROAN® interlocked make-up air dampers provide outside air, when required, to keep the air in the home fresher by allowing the range hood to operate at optimum levels BROAN® interlocked make-up air dampers provide outside air when required to keep the air in the home fresher by allowing the range hood to operate at optimum levels Slave dampers are interlocked to the main automatic or universal make-up air damper and open in unison for synchronized operation. They close, along with the main damper, as soon as the range hood is powered off. Slave dampers can be “ganged” together to provide a cost effective means to provide for higher volumes of make-up air Can be used to meet International Residential Code (IRC)-based requirements for make-up air See interactive Make-Up Air Specifier Tool for suggested model(s)