GSM Door Gate Opener System Remote On/Off Free Call SMS Command Excellent

Feature: \n 1. 850/900/1800/1900MHz four-band, can work in the global GSM network.\n2. No telephone charges. When the GSM relay switch receives the call from the authorized number, the first\n3. Security. Use caller ID for identification, unknown callers will be ignored.\n4. Add or delete users through SMS text commands.\n5. Relay action confirms the return message to the host or authorized call in the number. This function can be edited by the user. \n\nSpecification: \nThis GSM door opener has the function of remote switch. It can be operated from anywhere by authorized telephone call free of charge. There is no distance limit and it is very convenient.\n\nFeatures:\n\n--\n\n850/900/1800/1900MHz four-band, can work in the global GSM network. \n\n--\n\nNo telephone charges. When the GSM relay switch receives the call from the authorized number, the first \""ring \"" is switched on or off. \n\n--\n\nSecurity. Use caller ID for identification, unknown callers will be ignored. \n\n--\n\n: