First Alert CO400 Carbon Monoxide Alarm $10 at Amazon
Amazon has the First Alert CO400 Carbon Monoxide Alarm for
$10.29 with free shipping on $25+ or with Prime or free one-day pickup in select cities.
Walmart has it for
$10.77.
Features an electrochemical carbon monoxide sensor, silence/test button, low battery warning and a end-of-life timer.
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