is a plenum box for supply and exhaust air intended to achieve a stable flow to a rectangular grille or other types of face-plates. VBA is equipped with an adjustment damper and pressure measurement device. The plenum box can be connected from the side, the top or the back. The adjustment damper is operated from the front of the box by means of a graduated handle with integrated locking mechanism. VBA is equipped with a telescopic connection for easy installation. The same face-plate and telescope are used as for WB boxes. For more information, please contact This email address is being protected from spambots. You need JavaScript enabled to view it.