Talking Alarm announces the hazard type detected helping to speed up the reaction time. The date on the back of the product is the manufacture date, not the expiration date.
A single unit can be installed where previously two were needed
Battery Safeguard ensures the unit cannot be accidentally mounted without batteries installed

Battery operated (3-AA batteries included) – provides protection during power outage
Low battery signal – alerts user when the battery needs to be replaced
2 different mounting options: wall-mount or self-standing on tabletop

Independent type ceiling installation, simple installation
Import sensor, stable performance, high sensitivity
Sensor life permanent, long-term without replacement