INamedValues2 is an interface supported by NamedValues collections in PI-SDK 1.1 and later releases. It contains all methods and properties of NamedValues, as well as these additional methods:
MTNVS is a thread-safe version of NamedValues. It implements all the NamedValues and INamedValues2 methods and properties as well as native versions (prefaced by "MT") of the same.
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