Practical kit for work on air conditioning and refrigeration systems, as well as on heat pumps: the testo 557 digital manifold, including set of 4 filling tubes, enables you to get down to work straight away! The testo 557 digital manifold fulfils numerous functions in just one instrument: including superheating/subcooling calculation, vacuum measurement and temperature-compensated leakage test. You can also use a practical App to monitor the manifold via your smartphone/tablet and to store the measurement results or send them by e-mail.