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grain silo smoke detector direct from Wanlin Fire Protection — 12-year factory experience, WL-SFP900 smart fire detector 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 + 10-Year Design, 4G LTE Cat.1 + WiFi + Cloud Platform + Mobile APP + Complet···