Audiopipe, 18" Quad Stack Subwoofer Dual 4 Ohms. 18" Quad Stack 3400 Watts Max, Subwoofer, 340 Oz Magnet 2-Ohms -. Impedance: 2 x 4 Ohms. Voice Coil: 4" BASV 4-Layer Dual. Sensitivity: 90 dB. Powdered Black Paint Aluminum Basket.
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