4x PRV 12W750A 12" Alto Series Pro DJ/Studio Speaker Subwoofer Sub. 750W 8-Ohms.
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Dayton Audio PA310-8 12" Pro Woofer - Walmart.com
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Orion CO124D Cobalt Series 12" Dual 4 Ohm 1800 Watts Max Car Subwoofer — The Wires Zone