The AJAX-AD-RELAY-B is a wireless, low-current dry contact relay designed for remote control of various electrical devices within an Ajax security system. Operating on a 7-24V DC power supply, this compact unit features a potential-free (dry) contact that is galvanically isolated from its own power supply, allowing it to control both low-voltage and household networks. It supports bistable and pulse modes (with adjustable pulse duration from 0.5 to 255 seconds), making it versatile for applications such as electric locks, gates, rolling shutters, and even restarting modems/routers. Leveraging Ajax's proprietary Jeweller radio technology, it ensures secure two-way communication with the hub up to 1,000 meters in open space, protected by AES encryption and jamming detection.