Massive Audio UFO10 10" 600 Watt Dual 4 Ohm Shallow Mount Subwoofer — Big Jeff Online Inc
Pyle PLPW6D 6 Inch 600 Watt Dual 4 Ohm Car Audio Stereo Speaker Subwoofer, Black, 1 Piece - King Soopers
Amazon.com: Pyle Car Vehicle Subwoofer Audio Speaker - 6.5 Non-Pressed Paper Cone, Black Plastic Basket, Dual Voice Coil 4 Ohm Impedance, 600 Watt Power, Foam Surround for Vehicle Stereo Sound System -PLPW6D : Electronics
BOSS Audio Systems BE8D Elite Series 8 Inch Car Audio Subwoofer - 600 Watts Max, Dual 4 Ohm Voice Coil, For Truck Boxes and Enclosures, Hook Up To Amplifier