USPRO XD-11 Serial Transceiver Bluetooth Base Board Module for HC-05 06 07 bc04 For Arduino smart car robot Can install various common-used bluetooth module such as HC05\06\07\BC04 or other module support pin definition. Power anti-reverse design. It has delete button to support such module. Hign quality and reliable. The pin-outs include common TXD, RXD, STATE (if any) pin, easy to use