1. Hook your Arduino up to GSM/GPRS cell phone network with GPRS shield! You can use your Arduino to dial a phone number or send a text to your friend. 2. Features: GSM/GPRS module SIM900; Supports frequency band 850/900/1800/1900MHz; Support TCP/UDP protocols; Full control via AT commands set: Standard - GSM 07.07 & 07.05 and Enhanced - SIMCOM AT Commands; Power supply: 5~12V; I/O voltage: 2.8V; Default baud rate: 19200; The highest baud rate: 115200. 3. Applications: data transmission of Internet sensor; Automatic monitoring system; Pollution source remote monitoring; GPRS Weather information collection system; Industrial energy consumption monitoring; Warehouse monitoring management.