GSM Door Opener, Home Security Access Control Alarm System With Call/SMS Switch Remote Control

This GSM door opener has the function of remote switch. It can be used from anywhere by authorized and free phone call. There is no distance limit and it is very convenient. 850/900/1800/1900MHz, four bands, can work on global GSM network. No phone charges. When the GSM relay switch receives the call from the authorized number, the first "ringtone" is turned on or off. Security. Use Caller ID for ID, unknown callers will be ignored. Add or remove users via SMS text commands. There is no need to provide remote controls or keys for different users. Up to 200 authorized phone numbers can be set up within a specified timeframe. The relay action confirms the return message to the host or call allowed in the number. This function can be changed by the user. Relay switching time is programmable. Multiple applications, suitable for doors, pillars, fences, garage doors, shutters and doors or machines.