Harmony Audio HA-F104 Car Stereo Flatline 10" Sub 700W Single 4 Ohm Subwoofer Harmony Audio HA-F104 Car Stereo Flatline Series 10" Sub 700W Single 4 Ohm Subwoofer. The slim flat sub only requires a minimal amount of mounting depth and airspace so it can work in virtually any enclosure.
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