Features: WM150 is a Watt Meter, which is capable to test Voltage, power, current data of the electric equipment, like servos, etc. 1-50V power, current is up to 150A, the precise accurate to 10mA.USB firmware updates, easy to operate. Support PWM signal, 1us , the pulse width is changable by adjusting button. Automaticly to change unit of the capacity, when it is lower than1A, unit-display when it is higherthan1A, unit-dispaly is changed to A. The watt meter is also supporting to display working hours. Specifications: Item: WM150 Watt Meter Input Voltage: 1-50V Current: 150A (precision:10mA) USB: 5.0V1A ( USB3.0 firmware updates) Output: PWM1000-2000us@50Hz Display: 2.4" LCD Screen(320x240 resolution) Product Size: about 80x54x23mm/3.15x2.12x0.91in Net Weight(About): 120g Package Includes: 1Set WM150 50V150A Watt Meter note: Due to the problemsof lighting effectsand shootingangles, there mightbe certain tolerances in the product, please understand. Please allow 0-1cm error due to the manual measurment.