GTC CT8030 Dual Display Professional Automotive Multimeter Full auto range features with large selectable 4 or 3 digit main display and 4 digits secondary display as well as a 42 segments analog bar graph DC Voltage measurement up to 1000 Volt and AC Voltage measurement up to 750 Volt plus AC/DC Current measurement up to 10 A and Resistance measurement up to 40 Mohm Tachometer function with inductive pickup measures from 30 to20000 rpm plus dwell measurement in degrees from 0 to 360 degree or duty cycle from 0 to 100 percent Temperature measurement from -20 degree centigrade to 1000 degree centigrade or 0 to 1832 degree Fahrenheit Fuel injection test measures pulse width from 0.05 to 250 mS, or duty cycle from 0 to 100 percent and frequency measurement from 10 to 20 KHz plus oxygen sensor and alternator test function