Features: Include: a SMS module Voltage: 5V Frequency: 900 1800 MHz Stand by current: < 10 mA Working current: < 80 mA Baud: 9600 or change by sending AT+IPR=xxxx Interface: TTL Commands: Regular AT commands Connector: 5V GND TxD RxD Antenna: Please solder a copper wire to the board or use an IPEX socket Temperatures: -30 C to 80 C Functions: Send/receive SMS messages and GPRS data. Excellent for remote sensing, experiments, alarms and automatic data collection. The control port is a regular serial port. You may connect it directly with a microcontroller such as Arduin. Or you can use a USB to serial port adapter and send commands directly from a computer.