12 ZOLL Aktiv Subwoofer 5800 Watt Bass + Verstärker + Kabelset Auto Aktivsub

Most cars do not have a lot of extra space that can be used to position subwoofers. You go out and get yourself an under seat subwoofer. The best place to install a small powered subwoofer would be under the driver’s or passenger’s seat, behind the back seat or in the back seat.

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