Sennuopu Active Subwoofer Built-in Power Amplifier Speakers High Resolution Audio System Car Sub Woofer Install On Spare Tire - Subwoofers - AliExpress
Custom Invisible Subwoofer Enclosure for Your Spare Wheel Recess : 5 Steps - Instructables
diy subwoofer spare wheel install | diyAudio
For those of you who want more bass but don't want to sacrifice your spare tire or hatch space, I highly recommend this spare tire mount subwoofer : r/GolfGTI