Amazon.com: Sundown Audio SA-15 D2 15" 600W Dual 2-Ohm SA Series Subwoofer : Electronics
BOSS Audio Systems D12F Phantom Series 12 Inch Car Audio Subwoofer - 1000 Watts Max, Single 4 Ohm Voice Coil, Sold Individually, Low Profile, For Truck Boxes and Enclosures, Hook Up To Amplifier
MB Quart QSE-216 Q Series 6-1/2" 2-way component speaker system at Crutchfield