Fixed wireless terminal Simple to install and easy to maintain Network support: gsm 850 900 1800 1900 mhz Imei changing function.You can change the imei to any 15digital code. Highquality voice Wide voltage range & low power consumption Provide accurate antipolarity signal Support dtmf Support pc fax Call forwarding Caller id Support 2nd stage dialing Provide command sets from phone keypad Add prefixal code automatically: Skype: tinazhu Callback function: Barred telephone numbers can be set flexibly Locking wireless terminal, locking sim card, locking districts and locking network Industrial module Connection mode: rj11 phone sockets Enhanced high gains external antenna Backup battery (optional) Power on/off indicator Signal strength indicator