About this item Comprehensive Protection for Your Home: The smoke & carbon monoxide alarms protect against two major hazards—smoke and CO—giving you peace of mind knowing your home is secured Enhanced Detection Accuracy: Using a high-sensitivity photoelectric sensor for smoke and an electrochemical sensor for CO, this smoke detector carbon monoxide detector combo delivers highly accurate detection Instant Alerts with LED Indicators: The 3-color LED indicator system provides visual alerts for different levels of danger, so you can quickly assess the situation Audible Alarm for Immediate Action: The loud 85 dB alarm will notify you right away in case of smoke or carbon monoxide danger, helping you take immediate action User-Friendly and Hassle-Free Setup: With 3 AA batteries included, installation is simple, and the detector requires minimal maintenance to ensure optimal performance