Order process was simple and product arrived as scheduled. Installed the included battery, tested then mounted on wall where the old one was. Now I can only hope it works when necessary....fingers crossed that time never comes!! The previous one was replaced as a result of the end-of-life alarm feature. It was already in use when I moved into the house Nov 2016. I would reccommend.
October 10, 2022
Carbon Monoxide Alarm purchase
Our carbon monoxide alerted us that it was at end of life. We quickly replaced it thru First Alert. We have been fortunate to never need the alarm but we know of friends who are still alive because their First Alert woke them up. The order process was so easy and efficient.
September 8, 2022
Ordered exact same model to replace. Easy to install with existing mounting screws.
September 5, 2022
Thanks First Alert
Ordered product to replace expiring unit. Came very quickly, with an included battery and placed in previous position to protect the home. Great service.
November 8, 2021
First Alert Alarm
Replaced the original with the same type. Fast shipping and easy set up. Will replace with same when needed. Love it!
September 29, 2021
As promised, order arrived quickly, in mint condition. and with clear instructions as to how to set up and use it. The alarm worked perfectly the first time, and I have no doubt it will last as long as the one it replaced.
May 17, 2021
Couldn't Have Been Easier
I recently had to replace my First Alert CO detector. I decided to buy the same Model#. When did a Google search for that item, I was pleasantly surprised to find that the First Alert direct price was the lowest, and shipping was free. The whole ordering process was very easy, and I received the item quickly.
March 2, 2021
Basic Battery Operated Co2 Alarm-CO400
Ordered product directly for First Alert website...easy to navigate and simple order process. Received product within 3 days. Directions for install were thorough and straightforward.
James D Stewart
January 25, 2021
Fast and easy
I have ordered from this site before. It is easy to order and delivery is fast. Product arrived and is as described on the web site. Good product.
December 17, 2020
Very easy to order and fast service!
December 1, 2020
Always use first alert products. Very trustworthy and safe.
November 30, 2020
Works fine and easy to install
October 10, 2020
Fast delivery, packaged well, exactly as expected.
August 4, 2020
My order came in and seems to be operating well.
July 20, 2020
Nothing wrong with device, but was disappointed to find bolt holes not same distance be so I had to put in a new wallbolt.
July 6, 2020
Works as expected!
Received the item on time and it works as expected. Happy with my purchase thus far. One item to note: the placement of the screw holes in this model has changed in recent years, so while I was trying to avoid having to drill new holes by purchasing the same model as I was replacing, I did have to accommodate the change in design.
June 1, 2020
New CO400 to replace old CO400
Very good unit to purchase. One thing to note. The model number was the same as old CO detector we had, however new one would not mount on old mounting brackets. The screws were at different lengths so had to drill more holes in the wall. Would be nice if the model number had consistancy.
June 1, 2020
First Alert CO-400 Carbon Monoxide Alarm
This new CO detector is excellent. It replaces my previous CO-400 which needed to be retired after 8 years of reliable service.
It makes sense to stay with a winner.
The First Alert Store was a pleasure to deal with and they had my new detector in my hands within a week.
May 20, 2020
So far so good
Seems to be working OK after a month
May 10, 2020
The very BEST
Years of use...
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