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We have recently developed an adjustable louvre shutter, for one of our major customers who manufacture prefabricated plant rooms fitted with our DoorTechnik G15 industrial steel doorsets.

Ventilation louvres in the doors are a normal option, but we were asked to provide a means of manually restricting the airflow through the louvres during winter months. We tested several commercial shutters, but could not find one with all of the features needed, so we developed our own shutter assembly.


Locked in the closed position.


Turn to unlock, slide down to open.


Locked in the open position.












Only 20mm deep, the ALS13 is attached to a standard louvre’s inner frame, and can be easily locked in the fully closed or partially closed positions. Due to the ingenious internal design, the ALS13 naturally defaults to the fully open position, with a free area of 56%, which does not restrict the louvre’s 50% free area.



In the open position; shown with optional insect mesh.


Airflow is restricted in the closed position.