Loud 85-dB Buzzer When a threat is detected, this unit alarms using an 85-decibel siren to alert the entire household, even those with impaired hearing and/or in deep sleep. Built-In 10-Year Battery: Provides 10 years of continuous power with a built-in lithium battery, saving on energy while remaining eco-friendly; this smoke alarm and carbon monoxide alarm saves you from constantly having to change batteries or wonder if your alarm is still functioning.
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