The PTRTP 12 inch powered sub combines an active, award-winning CompRT subwoofer, a passive reFLEX sub, and a power-matched, built-in amplifier for an efficient, pounding bass solution for your ride. | Kicker | | PTRTP Powered Down-Firing 12" Dual-Voice-Coil-Ohm Loaded Subwoofer Enclosure | Black | Best Buy