--- product_id: 2536037 title: "CO400 Carbon Monoxide (CO) Detector, Battery Operated Alarm, 1-Pack" brand: "first alert" price: "R890" currency: ZAR in_stock: true reviews_count: 13 category: "First Alert" url: https://www.desertcart.co.za/products/2536037-co400-carbon-monoxide-co-detector-battery-operated-alarm-1-pack store_origin: ZA region: South Africa --- # Electrochemical sensor - 5 years accuracy 85dB alarm - loud & unmistakable alert 9V replaceable battery - power anywhere CO400 Carbon Monoxide (CO) Detector, Battery Operated Alarm, 1-Pack **Brand:** first alert **Price:** R890 **Availability:** ✅ In Stock ## Summary > 🏠 Protect your home, power your peace of mind. ## Quick Answers - **What is this?** CO400 Carbon Monoxide (CO) Detector, Battery Operated Alarm, 1-Pack by first alert - **How much does it cost?** R890 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.co.za](https://www.desertcart.co.za/products/2536037-co400-carbon-monoxide-co-detector-battery-operated-alarm-1-pack) ## Best For - first alert enthusiasts ## Why This Product - Trusted first alert brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Unmissable Safety Alerts:** Loud 85-decibel alarm ensures you and your family never miss a critical warning. - • **Trusted Legacy & Warranty:** Backed by First Alert’s 5-year limited warranty and UL certification—safety you can count on. - • **Precision Sensing Technology:** Advanced electrochemical sensor delivers reliable CO detection for up to 5 years without replacement. - • **Effortless Anywhere Placement:** Battery-powered design means zero wiring hassle—place it exactly where your home needs protection. - • **Smart Battery Life Management:** Audible and visual low battery signals keep you ahead of power issues for uninterrupted safety. ## Overview The First Alert CO400 is a battery-operated carbon monoxide detector featuring a highly accurate electrochemical sensor with a 5-year lifespan. It emits a loud 85dB alarm when dangerous CO levels are detected, ensuring immediate alerts. Easy to install with no wiring required, it includes smart battery alerts and a 5-year limited warranty, making it a trusted, hassle-free safety essential for every home. ## Description Product Description The First Alert CO400 carbon monoxide alarm uses an electrochemical sensor the most accurate technology available. The permanent sensor lasts up to 5 years. It is powered by a 9V replaceable battery giving you peace of mind even during power outages. The test/silence button silences the alarm and allows you to test its functionality. The unit monitors and re alarms if carbon monoxide level persist sounding a loud 85 decibel horn. No installation is required and the attractive design allows the unit to be placed anywhere you need it. It includes an optional wall mount with no outlet required. An audible and visual battery signal alerts you to replace the battery. Pull down action chart has convenient guide on what to do if an alarm sounds. 5 year limited warranty. Ul listed. desertcart.com Carbon monoxide (CO) is the leading cause of accidental poisoning deaths in America, yet many people don't know they are suffering from CO poisoning until its too late. Since symptoms of CO poisoning are like the flu, you might not even know you're in danger at first. That's why a carbon monoxide alarm is an excellent way to protect your family. It can detect the CO you can't see, smell or taste in the air. The First Alert CO400 carbon monoxide alarm uses an electrochemical carbon monoxide sensor-the most accurate technology available. The permanent sensor lasts up to five years. It is powered by on 9V replaceable battery giving you peace of mind even during power outages. The test/silence button both silences the alarm and allows you to test its functionality. The unit monitors and re-alarms if carbon monoxide levels persist sounding a loud 85-decibel horn. No installation is required and the attractive design allows the unit to be placed anywhere you need it. It includes an optional wall mount with no outlet required. An audible and visual low battery signal alerts you to replace the battery. Pull down action chart has convenient guide on what to do if an alarm sounds. 5 year limited warranty. UL listed. --Bree Norlander Manufacturer Contact Information 1 (800) 323-9005. Review: Simple, reliable, and essential for home safety - I recently purchased this First Alert CO400 detector to add another layer of safety to my home, and I’m very satisfied with the experience. What I appreciate most is the straightforward, battery-operated design. It was incredibly easy to set up—no hardwiring or complex installation required, which makes it perfect for placing exactly where you need it without worrying about electrical outlets. The unit feels sturdy and well-built, and the alarm is loud and impossible to miss. It provides great peace of mind, especially given how unobtrusive and reliable it has been since I installed it. For anyone looking for a no-fuss, effective way to monitor carbon monoxide levels in their living space, this is a solid, must-have product. Review: Great Carbon Monoxide Detector – Easy to Install and Reliable! - I bought two of the First Alert Carbon Monoxide Detectors (model CO400), and I’m very happy with them. They were super easy to install — no outlet needed since they run on batteries. I just mounted them on the wall, and they were ready to go in minutes.I like that the battery operation means I can place them anywhere in my home without worrying about finding a plug. The alarm is loud enough to hear clearly, and the design is compact and simple.It gives me peace of mind knowing my family is protected. Overall, great value, easy setup, and reliable safety product. Highly recommend! ## Features - Keep your family safe with this easy to use, battery operated carbon monoxide alarm; Battery powered alarms provide continuous monitoring of CO levels, even if there's a power failure - Features an advanced electrochemical carbon monoxide sensor that accurately detects carbon monoxide levels, no matter where the detector is placed in the room.The alarm sequence should last 5-6 seconds. If it does not alarm, make sure fresh batteries are correctly installed, and test it again. If the unit still does not alarm, replace it immediately - A loud 85 decibel alarm sounds when CO levels reach dangerous , Battery Replaceable - Yes - To ensure complete protection make sure to place one on each level of your home and in each bedroom - 5-year limited warranty; Equipped with end of life signal chirp, so you know when it’s time to replace the unit for safety - All first alert CO alarms are rigorously tested to meet UL standards - First Alert has been the most trusted brand in home safety since launching the first residential smoke alarm in 1958 (Based on a First Alert Brand Trust Survey in February 2018) ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B000N8OYXI | | Alarm | Audible | | Best Sellers Rank | #230 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #3 in Carbon Monoxide Detectors | | Brand | First Alert | | Built-In Media | Alarm; Mounting Bracket; User Manual; 9V Battery | | Color | White | | Customer Reviews | 4.6 out of 5 stars 22,878 Reviews | | Enclosure Material | Multi | | Global Trade Identification Number | 00029054000699 | | Item Dimensions D x W x H | 1"D x 5"W x 3"H | | Item Type Name | First Alert CO400FF Battery Powered Carbon Monoxide Alarm | | Item Weight | 0.45 Pounds | | Manufacturer | First Alert | | Manufacturer Contact Information | 1 (800) 323-9005. | | Manufacturer Warranty Description | 5 Year Limited Warranty | | Mfr Part Number | CO400 | | Model Number | CO400 | | Number of Items | 1 | | Operating Humidity | 10-95% RH | | Power Source | Battery Powered | | Product Dimensions | 1"D x 5"W x 3"H | | Product Style | Battery Powered | | Sensor Type | Electrochemical | | Style | Battery Powered | | UPC | 029054000699 | | Unit Count | 1.0 Count | ## Product Details - **Alarm:** Audible - **Brand:** First Alert - **Color:** White - **Global Trade Identification Number:** 00029054000699 - **Item Weight:** 7.2 ounces - **Operating Humidity:** 10-95% RH - **Power Source:** Battery Powered - **Product Dimensions:** 1"D x 5"W x 3"H - **Sensor Type:** Electrochemical - **Style:** Battery Powered ## Images ![CO400 Carbon Monoxide (CO) Detector, Battery Operated Alarm, 1-Pack - Image 1](https://m.media-amazon.com/images/I/51RBX7hitxL.jpg) ## Available Options This product comes in different **Pattern, Size** options. ## Questions & Answers **Q: Has anyone else received the CO400 with one 9 volt battery instead of the two AA batteries listed in description and on picture of packaging display?** A: Yes, Received the 9-Volt battery version. I live in California. I'm not a lawyer but my research shows that in California Smoke detectors and Combo Smoke/Carbon detectors must come with a 10 year lifespan battery. This law does not seem to apply to devices that only detect Carbon Monoxide like that one for sale here. **Q: Why can't this be purchased in or shipped to California?** A: I live in California. Yes, I received the 9-Volt battery version. I'm not a lawyer but my research shows that in California Smoke detectors and Combo Smoke/Carbon detectors must come with a 10 year lifespan battery. This law does not seem to apply to devices that only detect Carbon Monoxide like that one for sale here. **Q: the package picture shows 9-volt, but sounds like it is a crapshoot on what they will send you. which is better and lasts longer, 2AA or 1 9V? I hate taking out and putting in 9v batteries. so many to choose from. would prefer plug-in but would be too low.** A: I bought a package of AA batteries because this item description said it takes 2 AA. It does not. It takes (and comes with) one 9V. This is model CO400. **Q: Red light is on. Is that normal? Tested and it chirps with test. Also checked battery.** A: YEs, red light is normal. If red light blinks - read manufacturer's guide in link below. https://www.brkelectronics.com/pdfs/2017/10/23/803bf30c.pdf ## Customer Reviews ### ⭐⭐⭐⭐⭐ Simple, reliable, and essential for home safety *by J***. on May 20, 2026* I recently purchased this First Alert CO400 detector to add another layer of safety to my home, and I’m very satisfied with the experience. What I appreciate most is the straightforward, battery-operated design. It was incredibly easy to set up—no hardwiring or complex installation required, which makes it perfect for placing exactly where you need it without worrying about electrical outlets. The unit feels sturdy and well-built, and the alarm is loud and impossible to miss. It provides great peace of mind, especially given how unobtrusive and reliable it has been since I installed it. For anyone looking for a no-fuss, effective way to monitor carbon monoxide levels in their living space, this is a solid, must-have product. ### ⭐⭐⭐⭐⭐ Great Carbon Monoxide Detector – Easy to Install and Reliable! *by J***N on November 12, 2025* I bought two of the First Alert Carbon Monoxide Detectors (model CO400), and I’m very happy with them. They were super easy to install — no outlet needed since they run on batteries. I just mounted them on the wall, and they were ready to go in minutes.I like that the battery operation means I can place them anywhere in my home without worrying about finding a plug. The alarm is loud enough to hear clearly, and the design is compact and simple.It gives me peace of mind knowing my family is protected. Overall, great value, easy setup, and reliable safety product. Highly recommend! ### ⭐⭐⭐⭐⭐ Second purchase *by V***A on May 19, 2026* I did see some negative reviews but I purchased this for the second time because I did not have any issues. The last one was reliable. Lasted over 10 years and the only chirp was end of life 5 chirps and replace battery. We are very comfortable this is doing its job! ## Frequently Bought Together - First Alert CO400 Carbon Monoxide (CO) Detector, Battery Operated Alarm, 1-Pack - First Alert CO605 Plug-In Carbon Monoxide Detector with Battery Backup , White - Kidde Carbon Monoxide Detector, Battery Powered CO Alarm with LEDs, Test-Reset Button, Low Battery Indicator, Portable --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.za/products/2536037-co400-carbon-monoxide-co-detector-battery-operated-alarm-1-pack](https://www.desertcart.co.za/products/2536037-co400-carbon-monoxide-co-detector-battery-operated-alarm-1-pack) --- *Product available on Desertcart South Africa* *Store origin: ZA* *Last updated: 2026-06-25*