GSM 900/1800Hz, RS232 data, transparent data transmission,single data center or more, OverviewGPRS IP Modem is a data communication network terminal product ... /MMulti data center Cellular Module : Industrial cellular module;Network band: GSM 900 /1800 MHz, GPRS class 10;Interface: RS232 or RS485 ... 20X14.5X7cm (7.88X5.71X2.56 In) Typical Application W3100G Wireless IP Modem