TS-W310D4 - 12" Champion Series Subwoofer with Dual 4 Ω Voice Coils | Pioneer Electronics USA
Pioneer Champion TS-A301D4 | 12 Inch 1600W Dual 4 Ohm Car Subwoofer | TSA301D4 | eBay
Pioneer TS-W312D4 | Car Entertainment, Subwoofers, Champion Series Subwoofer, Champion Series Red Subwoofer | Pioneer Middle East - Car Stereo, Car Subwoofer, Amplifier