CPV code 35125200 designates Time control system or working time recorder in the Common Procurement Vocabulary (CPV 2008), the EU classification used to describe the subject of public contracts.
35125200 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 35125000 (Surveillance system).