Pioneer GXT-3730B-SET active subwoofer 12" (300 mm) kit.
Amazon.com: Pioneer TS-WX1210A 12" Sealed enclosure active subwoofer with built-in amplifier : Electronics
Pioneer DEH-S1250UB Single DIN AM/FM Radio USB AUX CD Player Car Receiver Bundle Combo with 12” High Performance 1350 Watts Peak Automotive Subwoofer, Class D 1500W Mono Amplifier, Amp Wiring Kit -
Audio Visual World - Pioneer GMD9601 with TWIN Pioneer TS-W311S4 with double 12 sealed subwoofer bass box and Amp kit