This value, in minutes, is the configured or actual length of the collection window for one specific, already-completed 24-hour (daily) bin, kept for day-over-day comparison. On this element it is what you divide the accompanying flood-containment drop byte and frame counters by to turn a raw cumulative count into a meaningful average rate for that completed day, and it is also how you spot a truncated bin -- one whose Duration reads less than the table's normal interval because a clear or restart cut it short. For a normal Hist24H bin this should read 1440 (24 hours in minutes); a value of 300 instead would mean the flood-containment drop counters only had 5 hours to accumulate, so a seemingly low total is expected and not a sign of quiet traffic.