It can be added if it is an outboard motor of a ship with a general structure.
The recommended amount of addition is approximately 5 to 10% of the oil for both engine oil and gear oil.
The effect can be maintained by adding a little more in the first time and adding 5% after the second time.
The features are the extension of the life of engine parts, the goodness of high rotation by reducing friction, and above all, the ability to avoid troubles when tides are mixed.
In addition, a lot of oil contamination stains appear only the first time after adding the additive, but since this occurs during metal surface treatment, oil stains will be less after the second time. (Even the first time, the amount of iron powder in the filter is extremely low.)