JBL Stadium 82SSI 400W RMS 8" Component Subwoofer with SSI™
JBL GX1200 GX Series 1000W RMS 12" Car Audio Subwoofer (Local Pick-Up Only)
Amazon.com: JBL Club WS1200 12" Shallow Mount subwoofer w/SSI (Selectable Smart Impedance) Switch from 2 to 4 ohm Bundled with Alphasonik Earbuds : Electronics
JBL Stage 1200D 12" Dual 2-Ohm 1200W Peak Power Car Audio Subwoofer Enclosure 50036381567 | eBay