Thermistor Gauge For 14010A Accurately Measures Vacuum Level from 25,000 to 0 Microns. An accurate indicator of the actual vacuum level within a system—you know exactly when the system is pulled down to a deep enough vacuum, saving valuable service time. More precise than most vacuum-type instruments available for field use, measures from 25,000 to 0 microns—telling you exactly when the system is ready to recharge.