This adapter harness package comes complete with both the inner and outer harnesses necessary for the effortless installation of LED Euro taillights into your MK6 Jetta. 
 
It is designed to work with both the pre-facelift and facelift models of the Jetta.
 
However, it is important to note that this harness is not compatible with facelift GLI LED taillights since the brake and signal functions are integrated into the same circuit, which makes the adapter harness unsuitable for those models.