Features: 1. No call charges. The 4GLTE Gate Opener rejects the call from authorized number and performs the ON/OFF action on the first ring; 2. Modern door operation method allows control without traditional remote devices; 3. Multiple applications including gates, bollards, barriers, garage doors, shutters, access doors, or machines; 4. Secure operation using caller ID for identification; unknown callers are ignored; no need to distribute remote controls to users; 5. Operable from any location with no distance limitation; add or remove users via SMS; Specification: Rated Voltage: 12VDC 1 A Working temperature: -10°C to +60°C Storage temperature: -20°C to +60°C Relative humidity: 10-90%, non-condensing 4GLTE frequency: B1, B3, B5, B8 Output Relay Voltage Rating: 6A/240V AC Supports up to 999 authorized phone numbers; Two digital inputs for door sensors, motion sensors, or other sensors to monitor doors and windows; when triggered, sends SMS alert and activates siren; One relay output rated at 6A/240VAC for connecting to door switches or machine controls; Relay activation can send SMS confirmation to owner; this feature is user-configurable; Operates on 4GLTE network for wide compatibility; Material: Metal Color: Blue Package Contents: 1 x GSM Gate Opener Note: Other items not included. Note: Light reflection and display differences may cause slight color variation between image and actual item. Measurement error allowed within +/- 1-3 cm.