SITERWELL Hardwired Interconnected Smoke and Carbon Monoxide Detector, 10 Year Product Life Alarm Smoke Carbon Monoxide Detector with 2 AA Batteries Back Up, Smoke and CO Detector Voice Alert, 5 Packs. ACCURACY IN ALARMING – Utilizes dual-light wave technology, it is more sensitive to detecting slow smoldering fires which produce light smoke. It can also distinguish non-fire smoke, reducing false alarms and keeping your cooking fun uninterrupted. WIRED OR WIRELESS CONNECTION – This smoke and carbon monoxide detector can be hardwired or wirelessly connected to can link up to 18, when any alarm is triggered, all alarms will sound and notify everyone of the emergency and notify everyone of the emergency. 10-YEAR PRODUCT LIFE – This fire alarms smoke detectors carbon monoxide combo with 2 AA batteries back up, providing protection in the event of a power outage. This alarm is designed for ten years of use with regular battery replacements. 2-in-1 PROTETION – This smoke detector and carbon monoxide detector, more accurate detection of smoke and carbon monoxide with dual sensors, providing an audible warning in excess of 85 decibels. DUAL LANGUAGE VOICE ALERTS – This hardwired interconnected smoke detector carbon monoxide detector allows you to choose between English and French for alarm notifications, ensuring all family members can quickly understand and respond. 5VA FLAME RETARDANT – The casing is made of plastic that’s conforms to 5VA flame retardancy standards, It withstands high temperatures, ensuring theprotection of internal electronic components.