Very good quality and very cheaper.
Features:

*locking onto a specified gsm carrier and service area is programmable
* support sim card locking (terminal refuses to take any other sim card except the one set to be accepted)
* designed for low power consumption and support li-ion battery and external dc adapter
* powerful encryption to ensure high security of data
* capable to retain operational parameters and data upon power breakdown
* provided with super password to access engineering mode for senior configuration
* support downloading parameter setting on the configuration program with a data cable
* support pc fax
* charge with charge meter
* polarity reversal signal

*change IMEI

Technical specifications
* gsm module dual band gsm 850mhz/900mhz/1800mhz/1900mhz
Signal receiving sensibility better than-105dbm better than-105dbm
Power output max:33+-2 dbm min:5+-5 dbm max:30+-2 dbm min:0+-5 dbm
* environmental temperature -10c to +60c relative humidity 0%to 95% noise <= 60 db(a) atmospheric pressure 86 to 106kpa
*electrical power consumption <= 2 watt
Operating voltage dc 12 v li-ion battery capacity 1850 mah
Battery cycle life 500 to 1,000 cycles
Quoted talk time > 3 hours
Quoted standby time > 15 hours
* structural dimensions 180 mm x 122 mm x 32 mm