ISR (Formerly ISIS performance) 3" Turbine Outlet O2 Housing - Nissan SR20DET S13 T25/S14 T28 or GT Series Turbo ISR (Formerly ISIS performance) Performance brings you the first True 3" Turbo outlet. Every other turbine outlet necks down, This new design from ISR (Formerly ISIS performance) Is a higher flowing true 3" outlet. Turbo Outlets increase exhaust flow and free up Horsepower. Great bang for the buck upgrade. Includes all gaskets and hardware required for install. This Specific Outlet has been double welded on the outside and inside to prevent cracking. Requires slight clearancing of bellhousing or flange. Due to the larger 3" diameter.