SECRUI Wireless Door Open Sensor Alarm Chime, 400ft Operating Range 52 Chimes Adjustable Volume with Mute Mode LED Indicators Magnetic Door Alarm Sensor for Home Store Office Security\n\n-- \uD83D\uDD14 Monitor Every Areas You Care with Wireless Magnetic Door and Window Alarm -- 400 feet long range far enough to cover every door and window in your house. The wireless and portable design allows you to install the wireless entry alert doorbell anywhere in your home, work, office, retail store or business. Each magnetic door / window sensor receiver can pair up to 20 door alarm sensors and each door sensor can add unlimited receivers. Different door sensors can be set to different chimes.\n-- \uD83D\uDD14 24/7 Lifeguard for Your Family -- The door alarm sensor will detect the door/window, and will be triggered to send out a signal when the door/window opening. This home security door alarm sensor chime when burglar opens door and helps deter break-ins. We use multi-color led reminders t.