Feature: The GPRS Shield is based on SIM900 module from SIMCOM and compatible with its clones. The GPRS Shield provides you a way to communicate using the GSM cell phonenetworks. The shield allows you to achieve SMS, MMS, GPRS and Audio via UART by sendingAT commands (GSM 07.07 ,07.05 and SIMCOM enhanced AT Commands). The shield also has the 12 GPIOs, 2 PWMs and an ADC of the SIM900 module(Theyare all 2V8 logic) present onboard. Quad-Band 850 / 900/ 1800 / 1900 MHz - would work on GSM networks in allcountries across the world. GPRS multi-slot class 10/8 GPRS mobile station class B Compliant to GSM phase 2/2+ Class 4 (2 W @ 850 / 900 MHz) Class 1 (1 W @ 1800 / 1900MHz) Control via AT commands - Standard Commands: GSM 07.07 07.05 Enhanced Commands: SIMCOM AT Commands. Short Message Service - so that you can send small amounts of data over thenetworks (ASCII or raw hexadecimal). Embedded TCP/UDP stack - allows you to upload data to a web server. RTC supported. Selectable serial port. Speaker and Headphone jacks Low power consumption - 1.5mA(sleep mode) Industrial Temperature Range - -40C to +85 C Size:8.5x5.7x2cm(approx) includes: 1 x GPRS/GSM Development Board Module