The Testo 549 digital manifold has two-way valve block, a large 2-line backlit display and sight glass, 60 refrigerant profiles, and a rugged design. It is designed to precisely measure high side/ low side pressure, instantaneously displaying the corresponding evaporation or saturation temperatures for 60 refrigerants. The Testo's rugged design provides dependable services for years. With optional temperature probes, Testo 549 digital manifold provides accurate superheat and subcooling calculations.