JBL GX Series 12" Single-Voice-Coil 4-Ohm Subwoofer Black GX1200 - Best Buy
JBL Club 1224 Club Series 12" component subwoofer with switchable 2- or 4-ohm impedance at Crutchfield
SSW-1 | Dual 15-inch (380mm) Passive Subwoofer
JBL PartyBox Encore | Portable party speaker with 100W powerful sound, built-in dynamic light show, included digital wireless mics, and splash proof design.
JBL GTO1504D Grand Touring Series 15" subwoofer with dual 4-ohm voice coils at Crutchfield