JBL Stadium 122SSI Stadium Series 12" component subwoofer with switchable 2- or 4-ohm impedance at Crutchfield
Replacement Speaker JBL M112-8 Woofer For JRX 112 Series Cabinets, 12" 8 ohms
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JBL GX Series 12" Single-Voice-Coil 4-Ohm Subwoofer Black GX1200 - Best Buy