Amazon.com: Gravity Car Vehicle Subwoofer Audio Speaker - 15 Inch Competition Grade Pressed Paper Cone, 2 Ohm DVC, Advanced Air Flow, 7000W Power for Stereo Sound System Warzone GW15D2 (2 Subwoofers) : Electronics
Amazon.com: NVX NSW122 Version 2 (NSW122v2) 700 Watt (350W RMS) N-Series V2 12" Dual 2-Ohm Car Subwoofer : Electronics