First Alert CO5120BN hardwired detector front view for quick installation.
First Alert CO5120BN with battery backup showing seamless power during outages.
First Alert CO5120BN interconnect setup demonstrates series-triggered alarms for whole-home protection.
First Alert CO5120BN alarm indicator lit highlights the unit that triggered.
First Alert CO5120BN mounting bracket and tamper lock ensure secure installation.
First Alert CO5120BN package includes alarm and 9-volt battery for quick setup.

First Alert

First Alert BRK CO5120BN Hardwired CO Detector with Battery Backup | 120V Interconnect

High-performance tools and home improvement made for confident daily results

$59.15

3 shoppers currently have this item in cart.

Low stock: only 5 left in inventory. Add to cart before it's gone.

Shop Pay installment options may appear at checkout where eligible.

Free shipping Secure checkout 100% refund eligible
Bundle & save Buy 2 and save checkout time

Premium tools and home improvement quality selected for United States (USA) customers.

Routine pack Build your routine pack (3)

Fast dispatch with always-free shipping and secure checkout on every order.

Free shipping

i

Free shipping on every order. Fast dispatch, tracked delivery, and secure checkout included.

Easy returns

i

Simple return flow and responsive support for eligible items.

Peak-demand shipping delays

i

During high demand, deliveries may experience short carrier delays. Tracking updates remain active for every order.

24/7 customer support

Questions before checkout? Our team is available and ready to help.

Return & RefundEasy returns and policy details Shipping PolicyDelivery process and tracking info
Share

Why customers choose TaskHolt Tools

Overview

The First Alert BRK CO5120BN is a 120-volt hardwired carbon monoxide detector that also carries a reliable 9-volt battery backup. Designed for bedrooms, hallways, and basements, it helps you stay aware of potentially dangerous CO levels without being overly sensitive to non-threatening fluctuations.

Smart sensing and smart alerts

With an electrochemical CO sensor and a microprocessor, this unit focuses on real danger while minimizing nuisance alarms common in busy homes. The integrated alarm horn reaches about 85 dB, so you know when action is warranted even if you are in another room.

  • Electrochemical sensor for accurate detection
  • Microprocessor control minimizes false alarms
  • Latching alarm indicator identifies the triggering unit

Power, interconnection, and coverage

Install with a plug-in power connector for quick setup and connect to 120V AC. The unit is inter-connectable with up to 12 other First Alert or BRK alarms and up to six compatible devices, so a single event can wake the entire system.

  • 12-unit interconnection and six-device compatibility
  • 9-volt battery backup provides protection during outages
  • Tamper-resistant mounting bracket keeps the device secure
  • Test/silence button to verify function and mute non-threats

Design, indicators, and usage

The bright LED indicators show power and alarm status, while a dedicated alarm indicator pinpoints which unit initiated the alert. The simple test function helps you confirm the unit’s functionality with a quick check.

What’s in the box

One CO detector, one 9‑volt backup battery, and a user’s manual, all UL-listed for residential use.

FAQ

Q: Can this detector interconnect with other alarms in a system?

A: Yes, it can interconnect with up to 12 alarms and six devices for coordinated alerts.

Q: How is the device powered and what happens during a power outage?

A: It uses 120V AC with a 9V battery backup to maintain protection during outages.

You may also like