The Testo 557s digital manifold with a 4-way valve block allows fast measurements on refrigeration, air conditioning systems, and heat pumps. It includes the Testo 552i Smart Probe for vacuum measurement and features a large display for result evaluation. Stored programs simplify measurements and automatically determine various system parameters. Bluetooth probes for temperature, vacuum, and humidity offer maximum flexibility. With the Testo Smart App, digital documentation can be handled on-site. Its proven quality and durability ensure consistent high performance in all conditions.