Xexun TK103-2 Quick Start Manual page 5

Two SIM card.
Unit will turn on for another one automatically When no fee with one SIM
card.
TF card*.
Support 2GB TF card, over-the-air update, resume from break point cannot
work without TF card.
Over the air update.
Update can be finished by SMS ,and also the software on our website will
be update occasionally
Breakpoint continuingly.
Date will be saved at SD card when in weak GPRS signal and will be send to
platform automatically again when have GPRS signal.