---

• + [PRODUCT] Smart Smoke Fire Alarm S1 series
• + [PRODUCT] Smoke Fire Alarm HS2SA-5 series
• + [PRODUCT] EN54-2/EN54-4 Fire Alarm Control Panel HM-920
• + [PRODUCT] EN54-2 /EN54-4 Fire Alarm Control Panel HM-921
• + [QUESTION] What kind of fire alarm host should we choose for linear smoke alarm 613PC ?
• + [QUESTION] Is interconnected sub-device’s SN the identifier for device?Why there is different SN for heat alarm and heat alarm recovery,also find different SN in fire alarm event?