Dorgard SmartSound Fire Door Retainer – Black Dorgard SmartSound is a wireless solution for legally holding open fire doors, automatically releasing them to close when a fire alarm sounds. SmartSound technology means the door units are not triggered by the noise of a vacuum cleaner. New SmartSound technology – not triggered by vacuum cleaners Three year expected battery life Carpet friendly – leaves no marks Can be fitted to any door No programming, just fit and forget Installed in under 5 minutes How Dorgard SmartSound works: Wireless technology battery powereFire doors can be held open at any angle Responds when alarm is activated As soon as alarm is activated, the plunger is released and the door will close
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