Vktech 8Pcs Wireless Window Door Magnetic Sensor Burglar Entry Alarm Home Security The perfect crystallization of the wisdom of science and technology essential outdoor leisure boutique Convenience in installation,Dustproof and insect prevention Super environmental suitability and stability Sensitivity, and without inadvertently touching, interference, so that it can effectively monitor the environment from a variety of account within the scope of its monitoring of human movement Has a convenient On /Off switch, so you can set the alarm to Off when you do not want to use it