Tronic Back Draught Damper 240mm Non-Return Flap

Our review

This is a pipe-connector damper with a flap that shuts on its own once airflow stops, so outside cold air and exhaust cannot travel back through the duct. It suits anyone running an extractor fan, kitchen hood or ventilation line where backflow is a nuisance, particularly in rooms that feel draughty when the fan is off. The key installation point is orientation: the flaps only seal properly when mounted horizontally, so check your duct run before ordering. Also confirm the 240mm size matches your pipe. Compare it with manual shutters or simpler gravity flaps, which may not close as cleanly.