This is the object's relative name (Rn) — just the last path segment of its Dn, the piece this EnvironmentParam instance contributes to its own address within the MIT tree. It holds the actual tunable value behind an environmental capability — for example the wattage budget a power-rebalancing feature is allowed to shift between chassis — separately from the feature record's own name and type. For this kind of object the Rn is typically built from the same identifying value as its Dn's final segment, e.g. the tail end of `sys/environ/environment-feature-power-mgmt/param-budget-watts`, so two sibling instances never end up with colliding addresses under the same parent.