Top 3 Selling Smoke Alarms: USI-MDSCN111

Why should I buy the MDSCN111?


This 4-in-1 alarm can detect & protect your home and family from smoke, fire, carbon monoxide, and natural gas. With just one installation, you can save your family from four deadly threats to a home.


This UL-Listed hardwired detection device is suitable for residential or commercial use. The MDSCN111 features a universal mounting bracket that makes it easy to install and great for new or replacement installations. This alarm features four LED lights that indicates which hazard was detected. In addition, USI Electric’s smart technology offers an alarm origination feature to assist you in determining the origin of the smoke, gas, or fire.



This smoke detector offers a universal smoke sensing technology that can detect slow fires up to 87% faster, as well as carbon monoxide, and natural gas. The alarm also features a self-diagnostic check to ensure operational efficiency. In addition, the MDSCN111 offers a LED light flash when it is time to replace the battery.

Power Outages

In the instance of a power outage, this unit includes a backup 9-volt alkaline battery for ultimate protection. The MDSCN111 also offers a battery drawer for easy replacement, without having to remove the detector from the wall or ceiling. Learn How Much Voltage Your Circuit Your Handle at Home

Battery Drawer

Battery Drawer for Easy Battery Replacement

Why should I purchase USI products?

USI Electric is a trusted manufacturer of high quality, easy-to install home safety products. With over 40 years of experience and service, USI’s mission is to launch products and technologies that work to keep families protected. USI Electric’s patented smart alarm technology makes their detection devices different than any ordinary alarm.

Their smoke detectors use a smoke sensing technology that responds to fires up to 87% faster. This technology can distinguish cooking smoke from a real fire, which can significantly reduce sensitive alarms that can be triggered by the slightest thing.

Does the USI MDSCN111 come with a warranty?

Yes—This smoke detector comes with a 7-year limited warranty.

Smoke Alarms Wear Out, Be Sure to Replace Them Before They Fail!

View Our Smoke Detectors

Recommended Reading

The top-selling USI-SS-770-24CC smoke alarm allows for easy installation and features a dual chamber ionization sensor that detects fires early. This alarm features an audible low battery indicator, a loud 85 decibel chirp, and an alarm and power test button.

The AC hardwired USI-1204 works great in both residential and commercial applications. This alarm comes with a protective cover and a backup battery in the case of a power outage.

Follow the owner’s manual instruction provided with any detection device, but, in general, you should perform a functional test of the smoke detector around the same time you maintenance elevators or windows. Find out ways to test smoke detectors in commercial buildings and how often to get them serviced!

Shakir Williams
Shakir Williams

A true creative with a penchant for the spiritual and natural order. She loves the Earth, almost as much as she loves writing about it.

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