tomzz Audio 4057-001 Speaker Installation Set Compatible with VW Golf 4 IV Passat 3BG Polo 9N New Beetle 165 mm Coaxial System TA16.5-Pro, multicoloured : Amazon.de
VW Golf 4 Subwoofer Fit-Box Holder by petrzmax - Thingiverse
VW Golf IV car speaker upgrade kit front and rear doors loudspeaker - Car Hifi Radio Adapter.eu