JL Audio 8W1v3-4 8" 20cm W1 Series Car Sub Subwoofer Driver 4ohm 150w RMS

It features shallow mounting depth (3.86 in. Lacking a pole vent, the rear of the motor structure can be placed directly against an enclosure boundary. Excellent excursion capability and linearity allow it to reproduce sub-bass with shocking extension and quality. ).

eBay