A check valve (or a backwater valve) is needed to prevent the reversal of airflow. At the same time, it also prevents insects or rodents from entering the ventilation system.
The installation is very easy: just push the internal check valve at a straight angle into the desired ventilation pipe.
Features:
External diameter (rubber seal): 125 mm
Material: galvanized steel panel
Number of valves: 2
Weight: 140 g
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