Features: 1. Free call charges. The 4G LTE door opener accepts calls only from authorized numbers and performs door opening/closing on the first ring. 2. Modern, hands-free operation—no physical contact or shaking required. 3. Suitable for multiple applications including gates, bollards, barriers, garage doors, rolling doors, access doors, and industrial equipment. 4. Enhanced security—uses caller ID for identification; unknown calls are automatically rejected. No physical remote controls needed for user access. 5. Remote operation without distance limitations. Authorized users can be added or removed via SMS. Specifications: - Rated voltage: 12 VDC, 1 A - Operating temperature: -10°C to +60°C - Storage temperature: -20°C to +60°C - Relative humidity: 10–90%, non-condensing - 4G LTE frequency bands: B1, B3, B5, B8 - Relay output rating: 6 A / 240 V AC - Supports up to 999 authorized phone numbers - Two digital inputs for door sensors, motion sensors, or other security sensors. When triggered, sends an SMS alert and activates the siren. - One relay output (6 A / 240 V AC) for connecting door or machine switches. Relay activation sends a confirmation SMS to the owner; this feature is user-configurable. - Designed for reliable performance across diverse applications using the 4G LTE network. Material: Metal Color: Blue Package Contents: 1 x GSM Door Opener (unit only; accessories not included)