JBL BassPro Hub | 11" (279mm) Spare tire subwoofer with built-in 200W RMS amplifier with remote control.
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
Genuine Volkswagen Audi - 000051419B - Spare Tire Mount Subwoofer Retrofit Kit (000 051 419 B)
Amazon.com: Gravity Warzone WZ10US 10" Pro Audio Active Compact Spare Tire Slim Aluminum 1000 Watts 2 Ohm Subwoofer Powerful Loud Speaker with Bass Volume Control Knob : Electronics
JBL BassPro Hub | 11" (279mm) Spare tire subwoofer with built-in 200W RMS amplifier with remote control.
Universal Fit Single 10" Subwoofer Sealed Replacement Spare Tire Custom Sub Box | 1X10-SPAREBOX
Amazon.com: CERWIN Vega 600 watts Active Spare Tire Application Subwoofers Series (VPAS12ST) : Electronics