1.Bench digital multimeter 4 1/2 digit 2.100kHz Bandwidth 3. RS232 interface ... voltage, DC current, AC current, resistance, frequency, period, conduction, dioxideMath function%, dBm, RELRangeAuto, ManualDisplayVFD,dual displayReading modeSingle display: all measurement parametersDual ... ALARM at HI/LO (selectable)Communication interface RS232C, SCPI Digital Multimeter TH1942