Features: Multifunctional True RMS Tester: it has the basic testing function of measuring AC/DC current, AC/DC voltage, resistance, capacitance, frequency, diode, on-off buzzer. More Features of TA803A: manual range, analog bargraph diaplay, average value measurement, diode test, triode test, NCV test, 1999 counts maximum display. More Features of TA803B: automatic range, diode test, MAX/MIN value measurement, temperature measurement, duty cycle/relative value, 5999 counts maximum display. Backlit Bright Screen for Clear Reading: HD bright screen with backlight ON/OFF switchable for display data clearly. Data Hold Function: hold the measured value for conveniently checking or writing down the result. Flashlight for Ausiliary Lighting: in the dark environment, flashlight lighting can be turned on to improve the maintenance efficiency. High Reliability Efficiency: intelligence prevent burn machine, LED buzzer alarm with good reliability and high precision, really practical for electrical equipment testing and maintenance. Soft Rubber Protective Sleeve Test Lead Slot Design: the tester was protect with a rubber case that is fall proof, dust-proof and shock proof. At the same time, the pen can be stored and protected to avoid accidental injury. Low Power Consumption Power Saving: powered by a 9V 6F22 battery(NOT included), and the tester will automatically shut down after 15 minutes of inactivity.