Sony XSGSW121D GS series 12" 4 ohm DVC subwoofer - EAI - Pascagoula
Amazon.com: Massive Audio ECO12S4 – 12 Inch Car Audio 500 Watt ECO Series Subwoofer, Single 4 Ohm, 6mm Top Plate, Steel Basket. Sold Individually : Electronics
DS18 High Excursion 15" Subwoofer Dual 4 Ohm 4000 Watts Max EXL-XX15.2 – Pricedrightsales
Audiofrog GS8ND2 GS Series 8" subwoofer/mid-bass speaker with dual 2-ohm voice coils at Crutchfield