Amazon.com: DS18 EXL-X15.2D Subwoofer in Black - 15" Speaker, 2,500 Max Power, 1,250 RMS Power, Fiber Glass Dust Cap, Red Aluminum Frame, Dual Voice Coil 2+2 Ohm Impedance, Treated Rubber (1 Speaker),
DS18 EXL-X8.4D 1,200W Max Dual 4-ohm 8" Subwoofer
Amazon.com: DS18 SLC10S Car Subwoofer Audio Speaker - 10" in. Paper Glass Fiber Cone, Black Steel Basket, Single Voice Coil 4 Ohm Impedance, 440W MAX Power and Foam Surround for Vehicle Stereo
DS18 EXL-XX15.2DHE High Excursion 15" Subwoofer 4000 Watts Max 2-Ohms DVC audio subwoofers