GSM GPRS SIM900 1800MHz Short Message Service m590 SMS Module DIY Kit For Arduino Specification: 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. Feature: 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 Arduino. Or you can use a USB to serial port adapter and send commands directly from a computer. If you also need a USB to serial adapter, please contact us. A complete instruction for using the AT commands will be provided. Package includes: 1 x DIY Kit