This is the parameter's key name — the label identifying which specific setting this Param row's Value field is holding. It holds the actual configured limit behind a server capability — for example the maximum number of vNICs a stateless-computing feature permits per blade — separately from the feature record's name. On this kind of record the name is typically something like 'max-vnics', so pairing it with the sibling Value attribute tells you which setting is at which number without needing a separate lookup table.