Ballwin Client Audi S3 Audio Upgrade Stage 1: Bass
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For Audi A3 8V B&O audio amplifier speaker subwoofer - AliExpress Automobiles & Motorcycles
M.A.P Audio & Customs - Custom made fiberglass 8" subwoofer enclosure for an audi a3 8v. This was hand made with mdf rings and support braces. It was then fiberglass and covered