This is the UART Serial Integrated Bluetooth HC05 Module, can be easily used Arduino transparent wireless serial port communication. This serial Bluetooth module is fully qualified Bluetooth v2.0 plus EDR or Enhanced Data Rate at 3mbps modulation with complete 2.4Ghz radio transceiver baseband. It uses CSR Bluecore 04-External single chip Bluetooth system with CMOS technology along with AFH (Adaptive Frequency Hopping Feature. These device is uses IO port to communicate can be expand to five analog IO that you can use it to connect other devices. This module can be configure as Master or Slave mode using AT COMMAND Set. Features• Arduino, RPI, BagelBone, STM, AVR Compatible. • Up to10m communication distance in house without obstacle• UART interface (TTL) with programmable baud rate (SPP firmware installed).• Default baud rate: 38400, data bits: 8, stop bit: 1, Parity: No parity.• Default Pairing Code:0000• A full set of configuration commands.• On board PCB antenna.