- Custom sized fitting to convert your FD3S oil cooler lines to -10AN Fitting lines for better cooling & refreshing old rubber leaky lines. - Hard Anodized T-6061 for durability - Includes O-Ring gasket for seal proof fitment **Fittings are sold individually. - For single OEM Oil cooler order 2 fittings - For dual oil coolers order 4 fittings.