Description: The Aerpro APP7230 20 Pin ISO Line Level & Trigger Adapter Harness enables an aftermarket headunit to be installed in various European vehicles with amplified audio systems from the late 1990’s to early 2000’s. Vehicles include various Audi models with OEM Symphony or Bose amplified systems, Porsche models with PCM 2.1 amplified systems and Mercedes models with OEM Blaupunkt amplified systems. This harness uses the RCA line outputs from the aftermarket headunit and has a blue amp remote trigger wire that connects to the aftermarket headunits amp turn on wire. Important Information Harnesses can vary between vehicle models, to find the correct part for your vehicle use the Aerpro Vehicle Selector. Aftermarket headunit requires front & rear RCA outputs. Features: Allows aftermarket headunits to integrate with vehicle OEM amplified systems in various vehicles Connects to the RCA line outputs and amp turn on wire on the aftermarket headunit Plugs into the vehicle ISO socket Specs: Harness Type: OEM Amplifier Retention Aftermarket Headunit Connection: 4x RCA Plugs & Amp Trigger Wire Vehicle Connection: ISO Wiring Configuration: Blue Cable: Amp Turn On / Trigger White RCA: Front Left Grey RCA: Front Right Purple RCA: Rear Left Green RCA: Rear Right Important Information: Harnesses can vary between vehicle models, to find the correct part for your vehicle use the Aerpro Vehicle Selector. Aftermarket headunit requires front & rear RCA outputs.