CPV code 38545000 designates Gas-testing kits in the Common Procurement Vocabulary (CPV 2008), the EU classification used to describe the subject of public contracts.
38545000 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 38540000 (Machines and apparatus for testing and measuring).