MTX Thunder5500 T5512-04 12" 4-ohm subwoofer at Crutchfield
TNP112D MTX Car Subwoofer Enclosure And Amplifier | MTX Audio - Serious About Sound®
Amazon.com: MTX TNP212D2 12 Inch 1200W Dual Loaded Car Subwoofer Audio, Sub Box, and Amplifier with QPower Super Flex 4 Gauge 3000 Watt Amplifier Wiring Amp Kit : Electronics