Amprobe AC9100V Electronic Vacuum System is a professional-grade vacuum pump designed for use in the evacuation and leak detection of air conditioning and refrigeration systems. It features an electronic vacuum sensor with LED indicators, an oil contamination sensor and warning light, a built-in isolation valve for leak checking, and an automatic purge to prevent rotor lock-up. The AC9100V is also equipped with an offset rotary vane pump design, a vacuum sensor/indicator that needs no calibration and is unaffected by temperature, an oil level window, and an extruded aluminum and ABS housing.