Feature: 1. 850/900/1800/1900MHz quad bands, compatible with worldwide GSM networks. 2. No call charges. The GSM Relay Switch answers calls from authorized numbers and performs ON/OFF actions upon the first ring. 3. Secure operation using caller ID for identification; unknown callers are automatically ignored. Specification: Overview: This GSM gate opener allows remote on/off control via free phone calls from authorized numbers. It can be operated from any location without distance limitations, offering high convenience. Features: - 850/900/1800/1900MHz quad-band support for global GSM network compatibility. - No call charges. The device answers incoming calls from pre-authorized numbers and activates the relay on the first ring. - Enhanced security through caller ID verification; blocks unauthorized callers. - Add or remove authorized users remotely via SMS commands. - Eliminates the need to distribute physical remote controls or keys. - Supports up to 200 authorized phone numbers with time-based access configuration. - Relay operation can send SMS confirmation to the owner or authorized number (user-configurable). - Programmable relay on/off timing. - Suitable for multiple applications including gates, bollards, barriers, garage doors, shutters, access doors, and machinery. Specifications: Model: 5034GSM GSM Frequency: 850/900/1800/1900MHz Network Support: 2G GSM SIM Card Type: Standard SIM card Digital Output: NC/NO dry contact, 3A/240VAC Power Supply: 9-24V DC, 2A Power Consumption: Max 50mA at 12V input, average 25mA Antenna: SMA 50 Ohm interface Operating Temperature: -20C to +60C Humidity Range: Up to 90% relative humidity Dimensions: 3.86 x 3.54 x 1.02 inches (98 x 90 x 26mm) Package Size: 5.12 x 3.74 x 1.18 inches (130 x 95 x 30mm) Package Weight: 4.87 oz (138g) Package Contents: 1 x GSM Door Opener 1 x User Manual 1 x Antenna