For measuring very small pressure differences with CASSY (5210.524013, 5210.524006, 5210.524018, 5210.524005W) or the universal measuring instruments (5210.531835, 5210.531836, 5210.531837), e.g. at flow experiments in the wind tunnel (5210.37312) or the Venturi tube (from 5210.373091). Connection to the experiment via two hose nozzles (4 mm diam.). Incl. PVC tubing (5210.667192) and two connectors with nipple (5210.604520).