OBD-II, the Second On-Board Diagnostics, is an automotive term referring to a vehicle's self-diagnostic and reporting capability. OBD systems give the vehicle owner or repair technician access to the status of the various vehicle subsystems.
The Cable is with one female head and two male heads. You can turn one OBD connect on your car into two with this cable to plug two CAN Bus board at the same time and make your project more powerful and creative.