Audio Adaptor For Audi A3 S3 A4 S4 TT Ground Loop Isolator Bose Active Rear Sub

Designed for adapting the Audi loom to RCA low input for use with BOSE or Active Sub System. It can also be regarded as an extension harness cable. The working principal is: It can isolate input and output circuits to prevent ground loop noise, enhance bass sound.

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