Amazon.com: DS18 SLC12S Car Subwoofer Audio Speaker - 12" in. Paper Glass Fiber Cone, Black Steel Basket, Single Voice Coil 4 Ohm Impedance, 500W MAX Power and Foam Surround for Vehicle Stereo
12" 1200W Dual 4-Ohm High Excursion Subwoofer - Phoenix Gold
Rockford Fosgate Punch P3D2-12 Car Subwoofer 1200W Max, 600W RMS 12" Punch P3 Series Dual 2-Ohm Car Subwoofer – absoluteusa