The Universal Security Instruments 3-in-1 Sensing Plus® Smoke, Fire, and Carbon Monoxide Alarm provides 10 years of continuous protection against deadly threats in the home. New Sensing Plus® Multi-Criteria Detection provides the benefits of both photoelectric and ionization alarms in one device to protect against fast-flaming and slow-smoldering fires. This combo alarm also offers protection against the silent killer-carbon monoxide, making it a three-in-one detector. The ideal addition for new or replacement installations, this maintenance-free alarm is suitable for houses, apartments, and mobile homes in every room.<br><br>This three-in-one alarm utilizes a sealed battery (included) that will never have to be replaced throughout the life of the detector, giving you a decade's worth of peace of mind, even in the event of a power outage. The 10-year permanent battery also saves money from battery replacements (up to $38.00 over the 10-year life of the alarm), eliminates annoying low battery chirps, and helps the environment by reducing environmental waste from disposed batteries. This combination alarm features microprocessor intelligence to assist in completely eliminating nuisance alarms, a single silence/test button to quiet a non-hazardous alarm, and an end-of-service life warning that sounds when it's time to replace the battery (approximately 10 years from activation).<br><br>Perfect for replacing existing Universal Security Instruments alarms, this combination detector features a large mounting base to cover imperfections in drywall and the option to replace retrofitting applications. The quick-activation battery pull tab makes it easy to install, while the deactivation key switches the alarm off and makes the batteries safe for disposal. Once the alarm is deactivated, the tamper-resistant feature turns on to prevent deactivated alarms from being reinstalled.<br><br>This detector conforms to UL 217 Standard 8th Edition and UL 2034 Standard 4th Edition. It has also been approved by the California State Fire Marshal and Federal Housing Authority (FHA) to exceed industry standards. New Sensing Plus® Multi-Criteria Detection provides resistance to false alarms from cooking, detection of polyurethane foam in both slow-smoldering and fast-flaming fires, and immunity to high-voltage current surges. For maximum protection, install an alarm inside every bedroom, outside every sleeping area, and on all levels. This alarm comes with a 10-year limited warranty that covers both the battery and alarm.