The Exhaust Air Shaft is made entirely of stainless steel and has a lower and/or upper rectangular opening with detachable grilles (fluff strainer). The cross-sectional dimensions of channels and hence the size of the fluff strainer results from the amount of the exhaust air and the room situation. A flush mounting of the fluff strainer is possible in any type of wall-panels. Connection to the existing ventilation system is approx. 50mm above the ceiling height.