The WM150 also supports PWM output with 1us precision - the pulse width is easily adjusted with the main control knob - making it an excellent servo and ESC tester.
|Input Voltage||1-50V DC (5V USB input required if input below 6V DC)|
This is a nice power meter, the LCD display is very useful (though the "3 bars" in the watt section are a strange UI choice). Not shown in the image is that peak values for amps and watts are displayed as well. Handy for computing max current draw and full throttle. Also has a built in servo tester so you can hook it up to an ESC and drive it directly from a dial on the side. Very handy device. I just used it in-line with my discharger to confirm that batteries were being drained to storage voltage at a safe rate.