Part numbers provided in the matrix in most cases are root part numbers.
Plenums and transitions are insulated with R4 1" liner unless otherwise indicated
The number after the dash on transitions indicates the length.
A suffix is required on most part numbers:
-24   For 24" long plenums
-36   For 36" long plenums
-48   For 48" long plenums
Include 'R8' for R8 lined plenums and transitions
Include the letter 'T' for R6 lined plenums
Include the letter 'U' for uninsulated plenums