Door/Window Alarm/Chime with Magnetic Sensor, Pack of 2

This entry alarm installs tool-free to nearly any door or window to notify you of any unwanted entry or exits. Especially great if you are monitoring kids or pets that try to wander outside without your permission. The alarm mounts w. double-sided adhesive tape. A magnetic sensor switch detects motion to protect your home or office & emits a loud beeping noise to notify you of any breaches to the perimeter. New & unused in package. Says batteries are included, but would recommend replacing since this has been sitting in our storage unit for an unknown period. - Pack of 2 sensors for two windows or doors - 90 DP plus @ 3 ft. sound level