Application Comp Adapter for T25 T28 GT25R, GT28, GT28R turbo, Bolt On to Compressor housing inlet and outlet. Spec. - CNC Billet Aluminum Flanges - Inlet Adapter is 2 Bolt, 2.5" OD - Outlet Adapter is 3 Bolt, 2" O.D Note Balanced on Schenck / Ready to use