ELI5: Explain Like I'm 5

Non-road engine

A non-road engine is an engine that is not designed to be used on roads. These engines are usually used in machines like construction equipment, agricultural machines, aeroplanes, ships, and other machines that are not designed to be used on roads. Non-road engines have different rules and regulations than ones used on roads because of where they are used and need special features to work in these environments.
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