Alarm Need 2 AAA Batteries to Operate ( Not Included );. Add More Remotes And Alarms. You Can Program Multi Remotes for One Alarm, Also Can Program One Remote for Multi Alarms;. Not Only a Safety/Antitheft Alarm, But Also a Doorbell, In Doorbell Mode, The Vibration Alarmdetects Vibration The Host Sound"Dingdong".
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