15" 38cm Sub Subwoofer Bass Car Audio 5000W 4Ohm DVC SPL SQL PERFORMANCE Heavy | eBay
Amazon.com: DS18 EXL-XX12.4DHE 12” High Excursion Car Audio Subwoofer 4000 Watts Dual Voice Coil 4 Ohms (1 Speaker) High Performance Big Bass Applications High Power : Everything Else
Amazon.com: DS18 PRO-BX18N.2D Car Subwoofer Audio Speaker - 18" in Neodymium Magnet, 6" Dual Voice Coil, 4 Ohm Impedance, 2500W Rms Power, 5000W Max Power - Reinforced Paper Cone for Outstanding Performance :