This is a professionally designed return ductwork installation kit for the BM24MCD (24000 btu) and BM36MCD (36000 btu) concealed duct (multi room) air handler. With the exception of the return plenum itself this kit includes all of the materials needed to successfully install the BM24MCD or BM36MCD return ductwork. This kit has been designed to deliver an optimal performance level and help to simplify the installation. It uses four 10 inch return ducts to optimize air mixture in your space. It is highly recommended that you select one of the matching supply duct installation kits as well and the supply and return air plenum KIT-BPK24 (24000 btus) or KIT-BPK36 (36000 btus). This kit is designed to be used with a ductboard plenum such as KIT-BPK24 or KIT-BPK36. This kit is not compatible with a sheet metal plenum. It includes:  

x4 25 feet of 10 inch R8 metalized felx ducts
x4 10 inch ductboard takeoff collar with no dampers
x4 14.5 x 14.5  x 10(round connection) Non insulated ceiling boxes
x4 14 x 14 x 1 ceiling filter grilles
x1 Foil tape