Dorgard SmartSound Fire Door Retainer

The SmartSound Dorgard which comes in black or white. The smarter fire door 'Keep Open' device. New technology means that the Smartsound uses audio filtering to listen for an actual alarm, reducing false activations by background noise, automatically releasing doors to close by a closer when a fire alarm sounds.
 
Accepted for use by fire authorities & complies with current BS standards
No programming, just "fit and forget"
Simple LED status lights
Carpet friendly - anti-drag feature
Daily timed release feature
Works with heavy fire doors (up to 160kg & 1600mm width)