This cable adapter only has 6 pins wired as above to support both ELD and/or Diagnostic testing. Used with 2013 or later models Volvo or Mack Heavy Trucks. Allows for connection of the 9-Pin GREEN OR 8/9 Pin BLACK Deutsch devices/cables diagnostic port on Heavy trucks to the 16-pin OBD-II type diag connector found in 2013 and later models Volvo/Mack heavy trucks.