Bosch F.01U.323.385 Instruction Manual page 6

The Gateway must be set up before the Smoke Alarms!
The forwarding of alarms from alarm to alarm and to mobile
devices will only work when the Gateway is switched on.
Up to 24 Twinguard Smoke Alarms can be connected to one
Gateway.
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Your mobile device must be on and connected to the internet in
order for you to receive warnings and information from your Twinguard
Smoke Alarm.
You can find more detailed information about your products and how
best to use them at:
www.bosch-smarthome.com
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