Pioneer Premier TS-W5000SPL at Onlinecarstereo.com
Pioneer TS-WX1220AH Dual 12" Ported Enclosure Active Subwoofer with Built-in Amplifier - Walmart.com
Pioneer 12" 1600 W Max Dual VC 4 Ohm Subwoofer - TSA301D4 | Reverb
Pioneer Premier TS-W8102SPL SPL Champion Series 15" 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