Provides a means of checking refrigerant temperature in the stream of gas. The most accurate method of testing gas temp is by sampling the refrigerant directly. Connects directly to a standard 1/4" flare access fitting. Remove, test and install the valve core from a 1/4" male flare access fitting without the loss of refrigerant, fast accurate measurements ensure to the degree temperature measurements for superheat or subcooling. A must have tool for the serious refrigeration engineer.