Overview:This GSM gate opener features remote on/off switch by authorized phone free calls, which can be operated from anywhere, no distance limit, very convenient. Features:*850/900/1800/1900MHz quad bands, can work in the worldwide GSM networks. *No call charges. The GSM Relay Switch answers the call from authorized number then carries out the turn ON/OFF action on the first 'ring'. *Secure - Using caller-ID for identification, unknown callers are ignored. *Add or remove users by SMS Text command. *No need to provide a remote control or keys for different users. *Up to 200 authorized phone numbers can be configured at the specified time. *The relay action will return a SMS confirmation to the owner or authorized call in number, this function is editable by user. *The relay close or open time is programmable. *Multiple applications. (Gates, bollards, barriers, garage doors, shutters and access doors or machines). Specifications:Model: G202 GSM Frequency: 850/900/1800/1900MHz Digital Output: NC/NO dry contact, 3A/240VAC DC Power Supply: 9-24V DC/2A Power Consumption: 12V input Max. 50mA/Average 25mA SIM Card: Standard SIM Card Antenna: 50 SMA Antenna interface Temperature Range: -20~+60C Humidity Range: Relative humidity 90% Item Size: Approx. 10.3 * 5 * 3.1cm / 4.1 * 2 * 1.2in Package Information:Package Size: Approx. 11.5*6.3*4cm / 4.5*2.5*1.6cm Package Weight: Approx. 97g / 3.4oz Package List:1 * GSM Door Opener 1 * User Manual Card