The AMR Turbo Back Exhaust for the 2008-2011 Subaru STI is one of the best systems out there! It is constructed from the highest quality U.S. stainless steel tubing and constructed here in the U.S. ensuring outstanding quality and durability. This unique turboback exhaust system from AMR features a 3in cattless downpipe and midpipe. The system splits after the center pipe into two 3in sections (unlike others which split into 2.5in piping) which leads to the canisters. The AMR turbo back finishes at the rear bumper with quad tips and is rated over 1,000 horsepower! There is an optional 1800 degree thermal coating which can be applied to only the downpipe & center pipe or the complete turbo back system from dowpipe up to and including the quad tips. The thermal coating keeps heat inside the pipe which speeds up exhaust velocity, reduces radiant heat, and protects the material.