1、The 4 frequency module is available worldwide. 2、Provides 2 antenna interfaces for compatibility with various needs. 3、Adapt to various main control boards. 4、The serial port is perfectly compatible with the microcontroller. The TTL serial port is compatible with 3.3V and 5V microcontrollers. 5、GPRS is based on module and is compatible with its clones. 6、GPRS gives you a way to communicate using a GSM mobile phone network. 7、The module allows you to implement SMS, MMS, GPRS and audio via UART by sending AT commands (GSM 07.07, 07.05 enhanced AT commands). 8、The board also features 12 GPIOs, 2 PWM and module ADCs (both 2V8 logic). Item Type:GPRS/GSM Development Board Quad-Band: 850/900/1800/1900 MHz - for GSM Networks in All Countries Worldwide. GPRS Multi-Slot Level: 10/8 GPRS Mobile Station: Class B GSM Compliant: 2/2 + Level 4 (2 W @ 850/900 MHz) Level 1 (1 W @ 1800 / 1900MHz) Control Via AT Commands - Standard Commands: GSM 07.07 and 07.05 Short Message Service - Allows You to Send Small Amounts Of Data Over The Network (ASCII Or Hex). Embedded UDP Stack - Allows You to Upload Data to a Web Server. Support For RTC. Optional Serial Port. Speaker And Headphone Jack Low Power Consumption - 1.5mA (Sleep Mode) Temperature Range -: -40℃ To +85℃ 1 x Module 1 x Antenna