GReddy Supreme SP Catback Exhaust Subaru STI Sedan 2011-2014 The legacy of the GReddy SP lives on with GReddys best version yet, the Supreme SP and to prove it carries a limited lifetime warranty! From the 1st flange to the new double-wall GReddy Tip, each Supreme SP system features a high-quality, hand Tig-weld 304 stainless-steel outer construction. Within the muffler, new straight-through and directed- straight-though chambered muffler designs allow GReddy to engineer a more refine exhaust note while increasing exhaust flow and performance. Classic GReddy street performance styling is maintained with excellent fitment and a stylish exhaust system layout. The Supreme SP not only designed to perform and sound great for each specific application; it matches the vehicles body-lines and styling.