Amazon.com: Pyle 6.5 Inch Mid Bass Woofer Sound Speaker System - Pro Loud Range Audio 300 Watt Peak Power w/ 4 Ohm Impedance and 60-20KHz Frequency Response for Car Component Stereo PLG64,Yellow : Electronics
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Amazon.com: H YANKA 12 Inch Subwoofer - 12 Inch Paper Cone Subwoofer Car Audio, Black Steel Basket, Dual Voice Coil 4 Ohm Impedance 12 subwoofer, 1600W MAX Power 12 inch Competition Subwoofer : Electronics