Amazon.com: Alpine SWA-12S4 BassLine Series 12" 4-ohm Subwoofer : Electronics
Car enclosed subwoofer 12 "30 cm ALPINE SWT-12S4 sound electronics columns 92dB subwoofers for cars acoustics auto audio parts components speaker - AliExpress
Alpine SWA-12S4 BassLine Series 12" 4-ohm subwoofer at Crutchfield
Car enclosed subwoofer 12 "30 cm ALPINE SWT-12S4 sound electronics columns 92dB subwoofers for cars acoustics auto audio parts components speaker - AliExpress
Alpine SWA-12S4 specifications
ALPINE SWT-12S4 Bass Test 20Hz (4k60fps) - YouTube