1.Wireless modem,industrial 2.GSM 900/1800MHz 3.Support SMS,Telephone,CSD 4.DB9 rs232 or 485 interface 5.Smallest ... build expensive fixed line network, saving cost substantially11.Reliable GSM network connectivity, providing fast and cost-effective long-range ... design with intelligent software capabilities, making it a reliable GSM solution for data collection and transmission Frequency:EGSM900 and ...