RPM104SL - 10" RPM Series Single 4 ohm Marine Subwoofer - Cerwin Vega
Garmin Fusion® FM Series Marine Subwoofers
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
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