(2500W RMS) The Z v.6 is the second step up in Sundown's "ultra-high excursion" subwoofer lineup after the X v.3 series and replaces the world-famous Z v.5 series.  All models (10,12,15,18) feature custom tooled and patented frames (US Patent Numbers D691596, D691597, D691598, and D741841).