Extra-S gear oil is what Subaru uses on all its high-performance models. According to Subaru, this fluid has the following benefits:
One quart bottle. (Note: Subaru uses at least two different bottle styles, which we have shown here. We don't have control over which bottle style they send us. The fluid will be the same in any case.)
Nomenclature note: Subaru used to sell a drivetrain fluid called "Extra S" that came only in five gallon pails. The five-gallon pails were discontinued and Subaru started offering this one-liter bottle instead. Subaru of America tells us this is the exact same fluid as the old Extra-S, which is why we advertise it with the Extra-S title.