Factory Amplifier wiring integration adapter with Antenna Adapter. Adapts a aftermarket RCA/Low Level output radio to the existing Factory Radio/Amplifier Harness. This harness allows the use of the existing amplified or premium sound system amplifier to work with an aftermarket stereo with low level RCA output jacks. This connects 4 RCA jacks, all necessary power and standard antenna connections to the factory harness. All wires are EIA (Electronic Industries Association Standards) color coded with stamped function on each wire. Includes 1 connectors with power and low level output RCA connector and correct antenna adapter cable. Includes wire color / function Instructions. 

IMPORTANT: FITS ONLY THE BMW YEARS AND MODELS in the Compatible Vehicles list above using FACTORY AMPLIFIED SYSTEMS ONLY...Thanks for looking.