A single NDC covering a carton that contains more than one component, each of which may carry its own inner NDC.
Adjuvanted vaccines, reconstitution packs and diluent-plus-vial presentations are all kits. The FDA lists the outer carton with dosage form KIT and describes the inner components in the packaging description text.
The outer kit NDC is normally the billable one. Submitting an inner component NDC is a frequent cause of quantity mismatches, because the payer prices the component rather than the dose administered.