Feature: 1. NIST Compliant Freezing Medium Database: Equipped with a built in database of pressure and temperature correlations for 90 refrigerants in accordance with US national institute of standards and technology (NIST) standards, this digital AC gauge provides accurate freezing medium temperature readings from pressure measurements, enhancing efficiency in freezing system maintenance and installation. 2. Advanced Digital Circuitry And Sensors: Utilizing state of the art digital electronics and high accuracy pressure sensors, the HVAC vacuum gauge accurately measures freezing medium pressures and vacuum pressure. This ensures accurate diagnostics and maintenance of AC and refrigeration systems for optimal performance. 3. Accurate Ball Valve Design: Featuring a ball valve design and high accuracy pressure sensors, the HVAC pressure gauge allows for accurate freezing medium charging, ensuring dependable and precise measurements. Its reliability makes it an essential tool for professionals in HVAC system maintenance. 4. Sturdy And Rugged: This HVAC vacuum gauge tester is made of excellent ABS and aluminum alloy material, which is sturdy and rugged, not easy to be damaged, and has a long service life. 5. HD Viewing Window: The digital vacuum pressure gauge includes a HD glass viewing window, making it easy to monitoring freezing medium move. This feature allows users to quickly and easily assess system conditions and make informed judgments during diagnostics and servicing. Specification: Item Type: Digital HVAC Gauge Material: ABS, Aluminum Alloy Working Mode: Freezing medium measurement mode, vacuum measurement mode, leakage measurement mode can measure vacuum percentage. Pressure Unit: KPa, Bar, PSI, InHg, KgF/cm Temperature Unit: , Pressure Measurement Range: 0KPa-6000KPa, Resolution: 1KPa Sensor Accuracy: 0.5% Overload Limit: 10MPa Operating Temperature Range: -20-60 Auto Shutdown: 10min (Can be set to start or stop, default start.) Battery: 9V 6F22 Battery x 1 (Not Included). Package List: 1 x Digital HVAC Gauge