Plug-and-play, isolated RCA input adapter harness to connect either version of the Harley Infotainment radio's REAR-SPEAKER-OUTPUT plug connection on the back of the radio harness, to the RCA inputs of most high-powered 12V automotive type audio amplifiers. Use this harness to bring the rear channels of the amplifier input gain controls into a useful range of adjustment, when setting up and tuning a high-performance Bagger audio system. This custom built J&M adapter harness will also remove the "speaker fault" condition when running the Harley radio diagnostics & eliminate any possible DC current that might otherwise travel between the Harley radio and the amplifier.; Special Note: This rear-speaker output connection point may not be active for certain Harley bagger models until a Harley radio flash is performed by your dealer to activate the front/rear fader control.