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USI Carbon Monoxide & Natural Gas Alarm, 120V AC Plug In

USI MCN400B
SKU USI-MCN400
USI Carbon Monoxide & Natural Gas Alarm, 120V AC Plug In

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USI Electrical Plug In Carbon Monoxide & Natural Gas Alarm features:

  • This new compact plug in alarm is perfect for new or replacement installations.
  • No Hardwiring Required.
  • 120-Volt AC Plug-In.
  • 9-Volt Battery Back-Up Included.
  • It provides protection against two deadly household threats: Carbon monoxide and natural gas (methane).
  • Its microprocessor intelligence is designed to eliminate nuisance alarms caused by non hazardous sources.
  • 5 Year Warranty.

USI MCN400B Description

USI Electrical Plug In Carbon Monoxide & Natural Gas Alarm features:

  • This new compact plug in alarm is perfect for new or replacement installations.
  • No Hardwiring Required.
  • 120-Volt AC Plug-In.
  • 9-Volt Battery Back-Up Included.
  • It provides protection against two deadly household threats: Carbon monoxide and natural gas (methane).
  • Its microprocessor intelligence is designed to eliminate nuisance alarms caused by non hazardous sources.
  • 5 Year Warranty.
Unlock FREE Shipping at $99 by just signing in!
Ships free on orders over $500 of eligible items to all guests.
Free Shipping Eligible
$46.54Each
Sold by the Case of 6 for only $279.24
In Stock-

Ships between 05/04/2026 - 05/18/2026

Product Specifications

Part NumberMCN400B
10-Year BatteryNo
Alarm Sensing TechnologyConventional
Alarm Sensor TypeCarbon Monoxide (CO), Natural Gas
Power TypeBattery, Plug-In
Sealed BatteryNo
Warranty5 Yr
Weight0.46-lb
UPC042741204002
Prop65
Important PROP 65 InformationWarning: This product can expose you to chemicals, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.p65warnings.ca.gov. to CA residents.
USI Carbon Monoxide & Natural Gas Alarm, 120V AC Plug In
Unlock FREE Shipping at $99 by just signing in!
Ships free on orders over $500 of eligible items to all guests.
Free Shipping Eligible
$46.54Each
Sold by the Case of 6 for only $279.24
In Stock-

Ships between 05/04/2026 - 05/18/2026

USI MCN400B Description

USI Electrical Plug In Carbon Monoxide & Natural Gas Alarm features:

  • This new compact plug in alarm is perfect for new or replacement installations.
  • No Hardwiring Required.
  • 120-Volt AC Plug-In.
  • 9-Volt Battery Back-Up Included.
  • It provides protection against two deadly household threats: Carbon monoxide and natural gas (methane).
  • Its microprocessor intelligence is designed to eliminate nuisance alarms caused by non hazardous sources.
  • 5 Year Warranty.

Product Specifications

Part NumberMCN400B
10-Year BatteryNo
Alarm Sensing TechnologyConventional
Alarm Sensor TypeCarbon Monoxide (CO), Natural Gas
Power TypeBattery, Plug-In
Sealed BatteryNo
Warranty5 Yr
Weight0.46-lb
UPC042741204002
Prop65
Important PROP 65 InformationWarning: This product can expose you to chemicals, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.p65warnings.ca.gov. to CA residents.

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