The RC2002A-GHG-ESV is a low-power radio transceiver module made by Raystar. It is designed for use in ISM band applications such as home automation, wireless sensor networks, and remote control systems. It is compliant with IEEE 802.15.4-2003 standards and operates in the 2.4GHz Industrial, Scientific, and Medical (ISM) frequency band. The transceiver contains an on-chip power amplifier, voltage regulator, crystal oscillator, PLL, and synthesizer to provide a low-power and low-cost system radio link. It supports BLE, Thread, ZigBee, and 6LoWPAN network protocols. The module is 3V powered and includes a General Purpose Interface (GPIO) to connect with other external devices. It also includes a built-in antenna and programmable preamble byte to ensure reliable communication.