Specifications:

• HC-05 Wireless Bluetooth Serial Transceiver Module Slave And Master Serial Communication For Arduino .
• HC-05 could be set to master or slave by user. HC-06 can only be master or slave which could be customized. Wiring(only need 4 wires): RX to RXD / TX to TXD / GND to GND / 5V to 5V
• Package included: 1 x HC-05 wireless bluetooth serial transceiver module
• Bluetooth module HC-05 Master and slave Two in one module
• Use the CSR BC417 mainstream bluetooth chip, bluetooth V2.0 SPP protocol standards
• Module working voltage 3.6 V to 6V
• Default rate of 9600,default pin:1234, the user can be set up. click the button into AT MODE
• Can be switched via AT commands as master or slave mode, the device can be connected via AT commands specified