Insert GSM SIM card, you can take the unit everywhere. And you can take it as normal PSTN phone when connect to telephone line. Big LCD display and friendly interface make it easy to operate. SMS Platform, polyphonic ring tone makes it more attractive DTMF/FSK Caller ID Short message receiving and sending Phone book : Up to 200 records Lock of long distance calls Locked to specified operator, cell lock, interlock of phone and SIM card Low voltage shock-resistant protection technique Call barring, call transferring, call waiting 128 x 64 LCD, backlight Language supports: English and Spanish Optional built-in/external antenna A large number of polyphonic ringing tones makes the Incoming call dynamic and the phone fashionable Network management by PMS Dialling local area code automatically Least cost routing Rapid service Inbuilt battery backup Standby time: 100 hours Real clock and calculator Displaying battery level and signal strength Quickly responds after pressing the keys