smart fire IoT hardware upgrade

smart fire self-built commercial property fire IoT direct from Wanlin — 12-year Chinese smart fire IoT manufacturer, WL-SFP900 certified UL 217/UL 268/UL 2034/UL 864/CE/EN14604/EN54/FCC. Key specs: Multi-Sensor (Smoke+Heat+CO) + 4G LTE + WiFi + Cloud Platform + Complete Installation Kit, 4G LTE Cat.1 + WiFi + Cloud Platform + Mobile APP + Complete Kit (Gatew···