Rev9Power Rev9_AC-084; Turbo Oil Drain Flange Adaptor For GT25/GT28/GT30 Turbocharger(-10AN) Product Details OIL DRAIN FLANGE ADAPTOR 10an "-aluminum t6061 -thread size 10an npt -fits gt25r , gt28r ,gt30r , and gt35r ball bearing turbo -bolt to bolt space 41.14mm "+fits most gt series and ball bearing turbo