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* Digital display displays the level of carbon monoxide the unit is sensing
* Three convenient mounting options
* Peak level button displays the peak CO level recorded by the alarm since it was last reset
* 9V Battery backup provides protection during power outages
* UL Approved
Amazon.com Product Review
Designed for residential use, the Nighthawk Carbon Monoxide detector keeps everyone in the house safe from poisonous, odorless CO fumes. The unit detects carbon monoxide levels from 30 to 999 parts per million. Its low-profile design doesn't stand out when connect to any wall outlet. The unit plugs directly into AC outlets for easy setup, and comes equipped with a 9-volt battery for backup during power outages. Its loud, 85-decibel alarm is sure to alert the whole house when safe carbon monoxide levels are breached. The Nighthawk is UL listed, and features a continuous digital readout of carbon monoxide levels, as well as peak-level memory display, and a test/reset button. It also can be stationed on a tabletop with the included 8-foot AC cord. The Nighthawk comes with a 5-year manufacturer warranty. --Brian D. Olson