30 return air support box with filter slot

FILTER SUPPORT BOXFILTER SUPPORT BOX - Manufacturer: Southwark Metal Weight: 30RETURN AIR SUPPORT BOX FOR FILTERS -

AirScape extra large return air filter box with grille 5 square feet face area for a low pressure drop Specifications:

return linear slot diffuser FILTER SUPPORT BOXFILTER SUPPORT BOX - Manufacturer: Southwark Metal Weight: 30RETURN AIR SUPPORT BOX FOR FILTERS -

return of the green knight slot Notice that filter slot near the middle of the photo Not only is air duct to the return side downstream of the filter Oops! When