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Amazon.com: Kicker 47TRTP122 Car Audio Down Firing 12" Thin Sub Box Passive Radiator Bundle with Harmony HA-A400.1 Amplifier & Amp Kit : Electronics
Amazon.com: KICKER 43CVR124 COMPVR 800W 12" 4-Ohm DVC Car Stereo Subwoofer Bundle with Rockville RS12 Single Subwoofer Enclosure Box and Single Sub Box Enclosure Installation Kit : Electronics
Amazon.com: (2) Kicker 44CWCS124 CompC 12" 600 Watt Single 4-Ohm Car Subwoofer Bundle with Dual Sub Box Enclosure Installation Kit and Rockville RD12 Dual MDF Sealed Subwoofer Enclosure (4 Items) : Electronics
Rockford Fosgate P3D4-12 12 inch 1200 Watt 4-Ohm DVC Car Audio Subwoofer and Q Power 12 inch Single Heavy Duty Vented Subwoofer Enclosure Box
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Amazon.com: BOSS Audio Systems CX122 1400 Watt Car Subwoofer, 12 Inch, Single 4 Ohm Voice Coil, 12 inch subwoofer Box Ready : Electronics
Kicker 44TCWC104 CompC 10" Truck Sub Box Enclosure 4 Ohm
Amazon.com: BOSS Audio Systems CX122 1400 Watt Car Subwoofer, 12 Inch, Single 4 Ohm Voice Coil, 12 inch subwoofer Box Ready : Electronics