FIRST ALERT Carbon Monoxide Alarm: Removable Battery, CO Detector
The FIRST ALERT CO400B is a carbon monoxide detector with an electrochemical sensor and a front-loading 9V removable battery. It features a sound alert at 85 dB @ 10 ft, a test button, hush mode, and a battery…
SKU 3G-OTH-551432
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Product Description
The FIRST ALERT CO400B is a carbon monoxide detector with an electrochemical sensor and a front-loading 9V removable battery. It features a sound alert at 85 dB @ 10 ft, a test button, hush mode, and a battery locking pin, meeting UL 2034 standards. Includes mounting anchors.
Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.
Frequently Asked Questions
What is the FIRST ALERT CO400B carbon monoxide alarm used for?
The FIRST ALERT CO400B detects carbon monoxide gas using an electrochemical sensor and sounds an 85 dB alarm at 10 ft. It is used in homes, offices, and industrial facilities to alert occupants of dangerous CO levels, helping prevent poisoning.
What are the specifications of the FIRST ALERT CO400B?
The FIRST ALERT CO400B features an electrochemical sensor, a front-loading 9V removable battery, and a sound alert at 85 dB @ 10 ft. It includes a test button, hush mode, battery locking pin, and meets UL 2034 standards. Mounting anchors are included.
Where to buy the FIRST ALERT CO400B worldwide?
3G Electric supplies the FIRST ALERT CO400B carbon monoxide alarm to customers worldwide. We handle full logistics, customs clearance, and delivery, ensuring you receive genuine FIRST ALERT products. Contact us for availability and lead time.
How to install the FIRST ALERT CO400B carbon monoxide detector?
Install the FIRST ALERT CO400B by mounting it on a wall or ceiling using the included anchors, at least 5 ft from the floor. Insert the 9V battery into the front-loading compartment, secure with the locking pin, and press the test button to verify operation.
Used in
Common applications for FIRST ALERTFIRST ALERT Products
3G Electric supplies FIRST ALERT carbon monoxide detectors. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.


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