Connect the Fieldpiece SSX34 Superheat & Subcooling instrument and add refrigerant until your superheat or subcooling reaches your target! The SSX34 automatically calculates superheat/subcooling for A/C and refrigeration systems. Displays pressure, temperature, superheat/subcooling. Calculations for R410A, R22, R134A, and R404A. Includes the ATC1 pipe clamp, K-type thermocouple, and a magnetic hanging strap. Visit www.fieldpiece.com or call 714/257-9060.— Fieldpiece