(4 pack) Universal Security Instruments, Sensing Plus, Combo Smoke, Fire & Carbon Monoxide Alarm, Multi-Criteria Detection, with 10-Year Battery, 4 Pack

3-in-1 Smoke, Fire & Carbon Monoxide Alarm provides 10 years of continuous protection against fast flaming, slow smoldering fires and carbon monoxide New Security Sensing Plus® multi criteria smoke & fire sensor uses AI-artificial intelligence techniques that can differentiate and classify smoke & fire profiles. 10-year lithium-free alkaline battery backup that provides a decade of peace of mind even when the power goes out. This smoke and fire detector has been Listed by the California State Fire Marshal and meets Federal Housing Authority (FHA) industry standards.