flush mount smoke alarm — Wanlin Fire, Chinese smart smoke detector manufacturer and exporter by Wanlin Fire Technology. WL-SD-500 photoelectric smart smoke detector with 4G LTE and NB-IoT dual-mode connectivity, 10-year sealed lithium battery, 85dB sounder, app/SMS/push alerts, remote cloud monitoring. EN 14604, EN 54-7, UL 217, CE, RoHS certified. MOQ fro···