Pioneer TS-A301S4 Champion Series12 Inch 1,600-Watt Max Single-Voice-Coil 4-Ohm Component Subwoofer - Walmart.com
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
Amazon.com: Pioneer TS-A301D4 Champion Series 12" 1600 W Max Power, Dual 4 Ohm Voice Coil - Component Subwoofer : Electronics
Pioneer Premier TS-W8102SPL SPL Champion Series 15" sub with dual 2-ohm voice coils at Crutchfield
Pioneer TS-A301S4 12" 4-ohm component subwoofer at Crutchfield
TS-W5000SPL - Premier 12" Competition SPL Component Subwoofer | Pioneer Electronics USA
Best Buy: Pioneer 12" Dual-Voice-Coil 4-Ohm Subwoofer TS-W307D4
TS-W261D4 - 10" Champion Series Subwoofer with Dual 4 Ohm Voice Coil | Pioneer Electronics USA
Amazon.com: Pioneer TSW312D4 Champion Series 12" 1500 Watt Dual 4 Ohm Voice Coil DVC Car Subwoofer : Electronics
Pioneer TS-W310D4 Champion Series 12" subwoofer with dual 4-ohm voice coils at Crutchfield