The 2-in-1 protection device, equipped with independently operating photoelectric and electrochemical CO sensors, alerts you immediately when dangerous smoke or CO concentrations are detected, while minimizing false alarms. This provides you with ultimate protection against two lethal threats in one device. Built-in battery with a 10-year lifespan A built-in lithium battery ensures 10 years of continuous operation, saving energy and being environmentally friendly. You won't need to change batteries or worry about whether your detector is still functioning. Precise, reliable, and highly flexible The X-Sense combination smoke and CO detector has been completely redesigned. It ensures that smoke triggers the alarm without interference by analyzing three separate smoke samples from the surrounding air. A 360° ring of air inlets guarantees complete detection without blind spots. LED status light The three-color flashing LED status light informs you about the operational status of the detector: the green LED indicates normal operation, the red LED indicates alarm status, and the yellow LED indicates a fault. This way, you and your home feel safe around the clock. The large LCD display shows the battery level and CO values in PPM (parts per million) from the surrounding air in real-time, with an update every 10 seconds.