This is Small SIM800L GPRS GSM Module Micro SIM Card Core Board Quad-band TTL Serial Port with the antenna, in this module two antennas have been included.

1. TTL serial port for serial port, you can link directly to the micro-controller.
2. Don’t need MAX232.
3. Power module automatically boots, homing network.
4. Onboard signal lights all the way.
5. It flashes slowly when there is a signal, it flashes quickly when there is no signal.