Pioneer Champion Series 12" Dual-Voice-Coil 4-Ohm Subwoofer Black TSW311D4 - Best Buy
Pioneer TS-W310D4 Champion Series 12" subwoofer with dual 4-ohm voice coils at Crutchfield
LAB SlapBox™ 2.25 ft^3 Ported MDF Enclosure for Single Pioneer TS-W3002D2 / TS-W3002D4 Sub
Pioneer RNAB01CMVA95A 2 x pioneer ts-300d4 12 inch 1400 watts max power dual 4-ohm voice coil car audio stereo subwoofer loudspeakers/free alphason
Pioneer TS-W3002D2 Champion Series Pro 12" sub with dual 2-ohm voice coils at Crutchfield
Amazon.com: Pioneer TS-A300D4 12 Inch 1500 Watts Max Power Dual 4-Ohm Voice Coil A Series Car Audio Stereo Subwoofer Loudspeakers / Free Alphasonik Earbuds : Electronics