NVX QBUS8P 300W Peak (150W RMS) 8" Amplified and Loaded Under Seat Quick Bass Universal Subwoofer System with Ported Enclosure - Walmart.com
Amazon.com: Passive Subwoofer, 150W High Power Passive Subwoofer, Home Audio Subwoofers, with 40mm Machine Base, for Home Theater Stereo System, 6.5 Inch, Black : Electronics