four wire connection

villa fire alarm system direct from Wanlin Fire Protection — 12-year factory experience, WL-SFP100 smart fire detector certified CE/EN14604/EN54/UL217/UL268/FCC/QCVN. Key specs: Dual-Wavelength Photoelectric Sensing + Infrared Scattering Chamber + 4G LTE Cat.1 Cellular Communication, 4G LTE Cat.1 + IoT Cloud Platform + SMS/Push/Email Alerts + Remote Monitori···

multi-family home smoke alarm direct from Wanlin Fire Protection — 12-year factory experience, WL-SFP200 smart fire detector certified CE/EN14604/EN54/UL217/UL268/FCC. Key specs: Photoelectric Smoke Sensor + Electrochemical CO Sensor + NB-IoT Cellular Communication + Multi-Sensor Fusion, NB-IoT + IoT Cloud Platform + Dual Alarm (Smoke + CO) + SMS/Push/Email ···