Defining "Closed System" For The Laws Of Conservation

per my fallible understanding, the sole difference between a closed and open system is that an open system is considered to include a surrounding context to and from which system components can transfer. A closed system seems to be a context to and from which system components cannot transfer to surrounding context. Logic seems to suggest that a closed system can therefore apply to either a sealed subset context or the superset since, in the former, no system components can transfer to or from the subset context, and in the latter, since a superset refers to "all that exists" there exists no surrounding context for system component exchange.