Gravity operated leaf-type backdraft damper. The KOL damper is designed to prevent the fl ow of air and non-explosive air mixtures, the aggressiveness of which in relation to aluminum and aluminum alloys is not higher than the aggressiveness of air with a temperature of up to 60° C, not containing sticky substances and fi brous materials, with a content of dust and other solid impurities in an amount of not more than 100 mg/m3, through branches to switched off fans (from switched off fans) when the latter are connected to collectors.

They are made only of rectangular cross-section;

Design: