Terminator 12" Series 4Ω Subwoofer | MTX Audio - Serious About Sound®
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Amazon.com: Planet Audio AC10D Anarchy Series 10 Inch Car Subwoofer - 1500 Watts Max, Dual 4 Ohm Voice Coil, Sold Individually, for Truck, Boxes, Enclosures, Use with Amplifier : Electronics
Dayton Audio MX15-22 15" Max-X High Excursion DVC Subwoofer 2 Ohms Per Coil