CPV code 60421000 designates Non-scheduled airmail transport services in the Common Procurement Vocabulary (CPV 2008), the EU classification used to describe the subject of public contracts.
60421000 is a leaf code — the most specific level of its branch — so it can be used directly as the main CPV code of a contract notice. If it does not quite fit, check the neighbouring codes under 60420000 (Non-scheduled air transport services).