Fangrui Product Details Amp Volt Dual Signal Generator: Multifunctional Signal Generator Kit Is To Generate Ampere Voltage By 1 Module, Which Generate 0/4 - 20ma Current Signal And 0-10v Voltage Signal Just By Rotating A Multi-cycle Precise Potentiometer, Simple And Handy. Clear Led Display: Our 4-20ma Signal Generator Has Bright And Clear 3-digit Led Digital Display Screen, Which Can Be Used To Monitor The Output Current And Voltage. You Just Need To Push The Switch Below The Monitor Easy To Switch The Display. Amp Volt Display Calibration: There Are Current And Voltage Display Calibrating Potentiometer On The Back Of The Module. If The Display Is Accurate, You Can Calibrate The Display Value Of Current Voltage By Yourself. Wide Application: Our Signal Adapter Can Be Used As Signal Generator, Valve Adjustment, Inverter Control, Plc Debugging, Panel Debugging, Led Testing, Simulating The Output Of Transmitter. Other Features: With Lcd Display To Display Frequency And Duty Cycle Value; With Case; Pwm Output, Can Set Frequency