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Harmony Audio 2X HA-C124 Car Competition 12" Sub 2200W Dual 4 Ohm Subwoofer New : Electronics - Amazon.com
Amazon.com: 2X Gravity 8 Inch 1000 Watt Car Audio Subwoofer w/ 4 Ohm DVC Power 8' Sub Pair - Feature Dual Voice Coil, Thick Magnet, Design for Car, ATV, Van, High Performance