The °Catalytic Stripper (CS) is a device used in particle number measurement systems to eliminate volatile and semi-volatile particles, ensuring only solid particles are counted. It is required in the PMP protocol (EURO 7, EURO VII) for accurate particle emissions testing to reliably remove all volatile components of the aerosol.  The ºCatalytic Stripper is now required in order to meet these measurement conditions, as the previous technology of a simple evaporation tube is not capable to reliably remove all volatile components from the aerosol, resulting in measurement artefacts and incorrect data and interpretation.