CPV code 60653000 designates Hire of boats with crew in the Common Procurement Vocabulary (CPV 2008), the EU classification used to describe the subject of public contracts.
60653000 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 60650000 (Hire of water transport equipment with crew).