Meross Smart Smoke Detector WLAN Fire Alarm with Hub Works with Apple HomeKit Bedroom Suitable Fire Alarm with Mute Switch and Self-Test Function Tested According to DIN EN 14604Smoke and overheating detection: In addition to smoke detection, it can also detect overheating. If the temperature is too high (54 70), a beep will sound to remind you. In addition, there is low battery warning. 85dB maximum alarm Alarm linking When the alarm detects smoke high temperatures, the alarms connected under the same hub beep to remind you. One hub can hold 16 meross devices (inh. sensors, detectors, thermostatic valves) at the same time.