This adapter cable allows a J1939 Scan Tool (a scanner designed to plug into the round J1939 9-pin Deutch connector on a vehicle) to be used with a J1939 equipped vehicle that uses a standard OBD2 style connector.
The adapter has an OBD2 Male connector (to plug into a vehicle's OBD2 connector) and a male 9-pin Deutsch J1939 connector (just like the J1939 connector on a vehicle to allow a scanner to plug into it).
