Features:

• Onboard two set power supply interface VCC5 5V power supply, VCC4 interface, 3.5v-4.5V power supply, optional power on self starting (default) and control start.
• Onboard SMA (default) and IPXmini antenna interface, SIM900A interface reserved reset.
• Size: 49*50mm.
• Weight: 38g
• Support 2, mobile phone 3,4G card
• Serial port circuit: support for 3.3V single chip microcomputer
• TTL serial port: support 3.3 and 5V single chip microcomputer.
• Antenna circuit: guarantee short and straight, so as to ensure the signal strength.

The computer can give early computer debugging USB module power supply, a very large amount of data under the condition of the recommended current more than 1A. Standby dozens of MA data can be set to provide dormancy, dormancy of 10MA low power. 

  
Package Included:

1 x SIM900A V3.9 kit
1x Power Cable
1x Antenna

Useful Links:

Learn how to use the SIM900A in your Arduino Project