This is a 3 pin Deutsch and 2 Pin Cummins diagnostic cable for the Nexiq USB Link 3 and USB Link 2. This is a 3 pin diagnostic cable used to connect your Nexiq USB Link 3 to Cummins engines with either a J1939 3 pin Deutsch or a 2 pin adapter. Includes alligator clips for connecting to a battery. Also works with USB Link.