An MRB disposition that approves a Serial Number or Lot Number of an item for use that is more restrictive than the Development Requirements stipulate. For example, a marginally performing part might be limited for use as Test Support Equipment, for non-combat conditions, or for a restricted number of operational hours.
Limited Use items require unique part marking (basically a new Part Number specific to the newly-defined usage, because the Limited Use item is no longer interchangeable with the original) , so limited use dispositions are a very poor outcome, and have a very significant logistics tail. But sometimes they permit use of expensive materiel that would otherwise be scrapped.