This read-only object reports which bit position within the P2mpSnapshotAttribute bitmask corresponds to the fourth attribute value captured in this snapshot, completing the set of up to four attribute identifiers available for a single capture. It lets an admin's tooling fully decode a snapshot that monitors as many as four RF attributes concurrently. For example, a comprehensive RF health snapshot combining power, quality, and two other metrics would rely on p2mpSnapAttr4Id to identify the last of those four tracked attributes.