Universal Car Stereo Vented Enclosure Single 12" Alpine R2-W12D4 Type – absoluteusa
Alpine RS-W12D4 | Pacific Stereo
Alpine 12 Inch Type-R Subwoofer (R-W12D2) | SK Customs Car Audio & Home Theater | Atlanta | Norcross | Duluth | John's Creek
Alpine R-Series RS-W12D4 12" Shallow Mount Subwoofer with Dual 4-Ohm Voice Coils
Amazon.com: Alpine R-W12D4 Car Audio Type R Series Sub Dual 4 Ohm 2250W Peak 12" Subwoofer and HA-SWKD Dual Subwoofer Sub Box Install Kit : Electronics
Alpine Type R 12' SWR1243D Subwoofer | eBay
Insane Bass From Two 12" Alpine Type R (SWR12D4) Subwoofers!! - YouTube
Alpine R2-W12D2 R-Series 12" subwoofer with dual 2-ohm voice coils - Breakers Stereo and Performance
Alpine SWR-1221D 12" Dual 2-ohm Voice Coil Subwoofer at Crutchfield