Amazon.com: Kicker Bundle Compatible with Universal Car C10 Comp Dual 10" Loaded Vented Port Sub Box Enclosure 2 Ohm : Electronics
Amazon.com: JINGERL 50W 4Ohm 8Ohm Car Subwoofer 4 Inch Woofers Speaker in Car Bass Speaker Long Stroke Loudspeaker for Automotive Sound Box IPC (Color : 1 pieces-4Ohm) : Electronics
JBL BassPro SL2 Active Subwoofer Car Underseat Bass Box, 125-Watt Power Amplifier : Amazon.de: Electronics & Photo
Amazon.com: Pyle PLMRW8 8-Inch Outdoor Marine Audio Subwoofer - 400 Watt Single White Waterproof Bass Loud Speaker For Marine Stereo Sound System, Under Helm or Box Case Mount in Small Boat, Water