Return Air Plenum, 19-3/4 x 20 x 24 in

Return Air Plenum, 1 in Lined, 23 x 20 x 24, 26 ga

Return Air Plenum, 19-1/4 x 21 x 24 in, For GE 21 in Air Handler

Return Air Plenum, 23 x 20 x 24 in, For RUUD 24 in Air Handler

Return Air Plenum, 20 x 24-1/2 x 24 in, For RUUD 21 in Air Handler

Return Air Plenum, 16 x 19-3/4 x 24 in, For RUUD 17 in Air Handler

Return Air Plenum, 16-1/4 x 21 x 24 in, For GE 17 in Air Handler

Return Air Plenum, 20 x 24-2/5 x 24 in, For RUUD 21 in Cabinet

Return Air Plenum, 20-1/4 x 23-1/2 x 24 in, For GE C Cabinet

Supply/Return Air Plenum, 19-1/8 x 11-1/8 x 36 in, For GE Large Packaged Unit

Return Air Plenum, 21-1/4 x 24-3/4 x 24 in, For GE Connect Large Cabinet