5Core 4 Inch Subwoofer Replacement 40W DJ Speaker Loudspeaker Wide Range Loud WF472DC 1pair | Reverb
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Amazon.com: Motorola ROKR 810 Wireless Bluetooth Speaker with Built-in Subwoofer - 40W Portable Speaker with Microphone - Connects to Smartphone, IPX4 Water Resistance, Integrated LED Lights, Smooth Sound : Electronics