EZ Digital DM-442B Digital True RMS Bench Multimeter is a 4 3/4 Digit, 40,000-count Digital tester that has an internal USB & amp RS-232C Interface. This meter can take Alternating Current TRMS or Alternating Current/Direct Current voltage and amp current TRMS readings. This tester has Data hold, Auto-off, Analog Bar Graph, and Full Overload Guard functionality.