Smoke and carbon monoxide tester carbon monoxide detector free with co sensor

​This product SR-821THS is an intelligentcombined carbon and smoke detector, which adopts micro-processing control and electrochemical sensor, featuring high stability, low power consumption and small sensitivity drift. It is mainly used in places where carbon monoxide gas leakage and fire may occur, ensuring personal life safety. More detail：https://www.firealarmfactory.com/carbon-and-smoke-detector.html