CPV code 50312310 designates Maintenance of data network equipment in the Common Procurement Vocabulary (CPV 2008), the EU classification used to describe the subject of public contracts.
50312310 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 50312300 (Maintenance and repair of data network equipment).