The Quectel M66FA-04-STD is an RF transceiver module designed for wireless communication applications. It operates in the frequency range of 850MHz, 900MHz, 1.8GHz, and 1.9GHz, making it compatible with various cellular networks. The M66FA-04-STD is a surface mount module packaged in tape and reel for easy integration into circuit boards. It has a voltage supply range of 3.3V to 4.6V and a power output of 2W, ensuring reliable and efficient transmission. With a data rate of 85.6kbps and support for Bluetooth v3.0, GSM, and GPRS protocols, this module enables seamless wireless connectivity. It features UART serial interface for communication and has low receiving current consumption of 1.2mA to 1.3mA. The M66FA-04-STD is an obsolete product, but it still offers reliable performance for legacy wireless applications. It is an ideal choice for IoT devices, industrial automation, and other wireless communication systems.