Ⅰ. Security: With the caller ID function, the authorized number is automatically identified and unknown callers are ignored, ensuring that only authorized users can remotely control the device. User management is achieved through SMS commands, without the need for physical remote controls or buttons, avoiding the risk of traditional remote controls being copied or lost. The authorization process is simple and efficient, and up to 200 users can be added, which is suitable for access control in homes, companies or multiple scenarios, greatly improving the flexibility and security of use. Ⅱ. No call charges: This device works over the GSM network, and call control is completely free. When an authorized user calls the device number, the system recognizes and immediately executes the on/off command within the ring, without actually answering the call, so no call charges are incurred. Only standard 2G SIM cards are supported, with simple settings and extremely low operating costs, making it very suitable for long-term remote control use. Ⅲ. Widely applicable: Multi-scenario support, widely used in access control systems, elevator control, garage switches, parking management, villa entrances and exits, warehouse gates, unattended communication rooms, base station equipment control, traffic management systems, remote power control cabinets and other places. Whether it is industrial control, security management, or smart home, it can provide a stable and reliable remote control experience, truly realizing multi-scenario compatibility and intelligent management. Ⅳ. Design: Industrial-grade standard, the device adopts a metal shell with a protection level of IP30, which is effectively dust-proof and foreign matter-proof. The structure is sturdy and has good system insulation performance, suitable for high-demand environments such as rail transit and power control. The compact body is equipped with a wall mount bracket, which is convenient for installation on the wall or in the control box, does not take up space, and has a simple and generous appearance, which is both practical and beautiful. Ⅴ. Global remote control: Supports quad-band, supports 850/900/1800/1900MHz quad-band GSM network, suitable for most parts of the world. Just insert a standard 2G SIM card and complete simple settings, you can remotely control it through your mobile phone, no matter where you are, you can easily achieve switch control, breaking the distance limit, and it is an ideal choice for cross-regional management and remote monitoring.