Universal Security Instruments MCN400B Plug In Carbon Monoxide and Natural Gas Alarm with Battery Backup

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Life is full of frustrating interruptions. Especially the ones that keep you from dying a happy woman.

Sylvia untied the sarong from around her waist and stretched out on the beach chair under the umbrella. This trip was exactly what she needed to clear her mind and recharge her [BEEP] batteries, so to speak.

She gazed out on the ocean and watched the waves roll in. If she closed her eyes, the gentle crashing of the waves would surely lull her [BEEP] to sleep. But for now, she was just enjoying the view.

The warm breeze tickled her [BEEP] sun-kissed skin. She took a deep, cleansing breath and exhaled slowly, letting all her [BEEP] cares rush from her body. The white [BEEP] sand caressed her feet, and she wiggled her toes to bury them deeper.

Just as she was thinking that she could use a [BEEP] drink, her personal steward Javier appeared at her side. His bright blue eyes were [BEEP] striking against his olive skin and black hair. Sylvia was mesmerized by his chiseled jawline and full [BEEP] lips. He leaned in close. She could feel his warm breath on her neck as he whispered seductively into her [BEEP] ear with his non-distinct Mediterranean accent:

"Lady Sylvia, there is something that I have to say to you."

"Yes, Javier?" Her body quivered with excitement.

"Something that I have been meaning to ask you for so long."


"Something that I think we both have been wanting."


"Your [BEEP] carbon monoxide and natural gas alarm. Can you PLEASE change the battery already? It's driving me crazy!"

Sylvia awoke with a start and sat up straight in bed. She gazed blurry-eyed up at the alarm and cursed the low battery indicator. She stood up to take a closer look.

Of the three LED lights, the only one illuminated right now was the power. She pressed the test button and cringed as it beeped directly in her ear. It was still working properly. She would just need to replace the 9-volt battery soon.

She tucked herself back under the covers and tried to make the best of what time she had left before her alarm clock went off. At least she wasn't going to be dying in her sleep from gas poisoning any time soon. Though with the direction her dream had been heading, it wouldn't have been a bad way to go.

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  • Dual sensing alarm - provides protection against two deadly household threats: Carbon Monoxide and Natural Gas
  • Combination alarm is designed to detect the toxic carbon monoxide fumes that result from incomplete combustion, such as those emitted from appliances, furnaces, fireplaces and auto exhaust
  • It also detects the presence of natural gas, a common energy source often used for cooking, home heating and water heating
  • This compact plug-in alarm covers only one outlet and is ideal for every room of your home
  • Fast and easy to install, simply plugs into a standard outlet, no additional mounting required
  • Three LED colors indicate: Power, Carbon Monoxide and Natural Gas
  • Early warning of carbon monoxide and natural gas is best achieved by installing dual sensing alarms on every level of dwelling, including basements
  • For maximum detection, install alarm inside every bedroom, outside every sleeping area, and on every level of the dwelling
  • Microprocessor virtually eliminates nuisance alarms caused by non-hazardous sources
  • Features a Silence/Test button along with a low battery indicator
  • End-of-service life warning in approximately 7 years
  • Included back up 9-volt Energizer alkaline battery provides continuous protection

View product manual here

Warranty: 5 Year Universal Security Instruments


Sensor Type: Solid State, Metal Oxide
Primary Power: 120 Volt AC 60 Hz
Battery Backup: 9 Volt Energizer Alkaline Battery (included)
Audible Alarm: 85 dB at 10 Feet
Temperature Range: 0° F to 120° F (-18° C to 48° C)
Humidity Range: 10% to 95% RH
  • Power
  • Carbon Monoxide
  • Natural Gas
Size H 4.38" x W 1.55" x L 2.50"

In the Box:

  • (1) Universal Security Instruments MCN400B Carbon Monoxide/Natural Gas Alarm with Battery Backup


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Purchaser Experience

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  • 25% < 25 woots
  • 38% ≥ 25 woots

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  • 15% one year old
  • 80% > one year old

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  • 28% bought 2
  • 15% bought 3

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USI Plug In CO & Natural Gas Alarm
$22.99 Sold Out Home & Garden
$22.99 USD false 1 Retail EA
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4121 International Pkwy Carollton TX 75007 U.S.A.