1039933 Battery Operated Carbon Monoxide Alarm

SKU: 1039933

1039933 Battery Operated Carbon Monoxide Alarm

SKU: 1039933

  • CO detector alerts you to carbon monoxide
  • Battery-operated design works almost anywhere
  • Loud 85-decibel alarm sounds when CO levels are detected
  • Single test/silence button for simple operation


The First Alert CO400A Carbon Monoxide Alarm utilizes an electrochemical carbon monoxide sensor that lasts for up to five years to detect carbon monoxide. This carbon monoxide detector is battery operated, making it portable and easy to use anywhere, even in the event of a power outage. When carbon monoxide levels become elevated, a loud 85-decibel alarm alerts you to the threat.

Alerts You to CO Threats

The First Alert battery-operated carbon monoxide alarm uses an advanced electrochemical CO sensor to detect elevated carbon monoxide levels. When CO is detected, the carbon monoxide detector sounds an alarm to warn you of the threat.

Warning Features

When carbon monoxide levels are detected, the carbon monoxide detector sounds an 85-decibel siren . A low-battery light and alarm alert you when battery power is running low, and an end-of-life warning lets you know when the detector should be replaced.

Simple and Easy to Use

The First Alert Carbon Monoxide Alarm is easy to set up. Simply insert the battery, and the CO detector will start to monitor your space for carbon monoxide. There are no complicated displays or settings to navigate, a single button silences the alarm and tests the CO detector.

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Product Manuals

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User's Manual for CO400A Carbon Monoxide Alarm (English, French Canadian)