Formulated specially for 4 stroke outboards. Outboards typically operate at 5000-6000 RPM at wide open throttle, almost twice as fast as 4 stroke car engines.
Normal automotive lubricants are not formulated to handle these speeds. Quicksilver 4 stroke outboard oil contains special additives making it ideally suited for this application.
They help reduce wear, scuffing and scoring, prevent the formulation of rust and sludge and inhibit the formulation of unwanted damaging foam