The switch is an electrical switch operated by an applied magnetic field.Designed for use with alarm systems.Embedded in door or window frame, perfect for residential or commercial use.Great for use in family and factory window, door. etc.With double-sides tape design that for easily install.100% new and high quality.Switch Type: NC(normal close type), circuit is connected when magnet is near the switch.Normally closed: When the solenoid is closed in the vicinity of the switch in the normal position, opens the loop, and if the magnet is removed, the loop is pulled closed.Item Type: Door Sensor Magnetic SwitchModel: -38Material: PlasticColor: WhiteCable Length: 26cm/10.24in (.)Rated current: 100mARated voltage: 200V DCOperating distance: more than 15mm, less than 25mmRated power: 3WConnecting mode: NC. (normally closed)Package includes:5 x -38 Wired Door Window SensorOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.