Fully Integrated Retrofit Solution For Most 1St Company And Amana Vtac Plenums Includes All Necessary Hardware Except Ravdplat To Be Ordered Separately Drain Plumbing Included Works With V10, V11, And V12 Models Make Up Air Ready With Optional Make Up Air Port For V12 Models Heavy Duty Galvanized Steel Powder Coated Construction Ul Listed Designed To Work With 1St Company And Amana Plenums That Are 21 3/8″ W X 43 3/4″ H X 5″ To 20″ Deep