Alpine Halo S-Series S2-SB12V 12" Linkable Ported Subwoofer Enclosure with 600 watts RMS power. The feature of dual 4ω voice coils wired in parallel for a 2ω load, kevlar-reinforced pulp cone, and Santoprene rubber surrounds with a peak power of 1800 watts and 600 watts RMS.
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