Product Overview A'PEXi 191KF201 N1 Evolution-R Muffler Pipe Diameter 3.0" -> 2.5" x 2 Tip Diameter 115mm Tip Quantity Dual 2008-2014 Subaru Impreza WRX STI Hatchback (GRB/GRF) 2011-2014 Subaru Impreza WRX Hatchback (GRB/GRF)