BMW HI-FI amp connector harness for upgrading to aftermarket amplifier. Please note this amp connector harness will only work with OEM 42-pin Hi-Fi AMP connector and will not work on vehicles equipped with Harmon Kardon (HK) sound system. It is designed for plug-n-play application without cutting or splicing factory wiring harness for installation of aftermarket amplifier(s). All wires are thin-walled automotive wire specification meeting or exceeding OEM wire size, 18 AWG for all signal and output wires and 12 AWG for subwoofer output wires. Signal wires are equipped with high quality gold plated metal male RCA connectors, not the cheap plastic one. All wires are crimped and soldered to ensure secure connection. Two different configurations are available for specific installation needs. The basic version comes with four channels signal output (FL, FR. RL, RR) and a remote wire. It is designed for those who just want the singal wires from the IDrive unit and run their own speaker wires for high power application. The deluxe configuration utilizes all existing OEM wirings for plug-n-play installation for full seven channels if desired, (Front left, Front Right, Center, Rear Left, Rear Right, Left Sub, and Right Sub). Both version can be configured with optional relay for multiple amps/dsp remote turn on application. All wires are labeled and come with connector pins assignment documentation. Basic version is USD, deluxe version is USD, and add for optional remote relay. The amp connector harness is compatible with 2005 and up E90/F10/F20/F30 series vehicles with Hi-Fi AMP. Earlier vehicles may have different pins assignment using the same connector, custom configuration is available if factory connector pin out is provided. Please request an invoice when ordering the deluxe configuration and or with relay.