Amazon.com: Pyramid 12 Inch Car Subwoofer Speaker - 500 Watt High Powered Car Audio Sound Component Speaker System w/ 1.5 Inch Kapton Bobbin Voice Coil, 8 Ohm, 25 oz Magnet, Cloth Edge
Amazon.com: Seismic Audio - SA-SBL124-12 Inch Dual 4 Ohm Slim Mount Car Audio Subwoofer 500 Watts Max Power : Everything Else