Features1Efficient Alarm: Even a slight vibration can trigger the alarm, more sensitive, can be a good protection of your property and items. 2Wide Application: Wired rolling shutter door magnetic alarm can be used for different types of doors such as rolling gates and rolling shutter doors. 3Easy Installation: No need for complex circuit connection, just simple installation can be enabled, providing you with convenience. 4Strong Adsorption Force: The magnet end uses strong magnetic glue, and the induction is more sensitive. 5Anti Theft Function: Effectively prevent theft and intrusion, to protect the security of the home and the store, is a very practical tool.SpecificationItem Type: Door Magnetic Contacts Switch SensorWeight: 168g/5.9ozSensing Distance :50-70mm/2-2.8inMaterial: Aluminum alloy silver gray platingSuitable for Working Voltage: 12VApplicable to Working Current: 500maContact Mode: (NC\NO) Normally closedInstallation Mode: buried, surface installationScope: Applicable to all kinds of rolling shutter doorsPackage List1 x Magnetic Contact Switches 4 x Screws 1 x Accessory