Like several other FNIRSI products I've purchased from Elektor, this power supply appears to be well built, with useful features, and a handy addition to my design space. However, there are issues with the instruction manual vs. actual operation of the power supply. First of all, one of the product photos shows the unit displaying a graph of voltage vs. time, yet there is no mention of this function in the manual, nor can I find any way to activate it if it even exists. And second, the six (6) presets for voltage and current cannot be saved using the instructions provided; after a lot of trial-and-error, I discovered the *next* preset (not the one currently displayed) can indeed be saved by pressing and holding the "M" button. Also, the button labelled with the usual symbol for ON/OFF does *not* turn power to the unit on and off; it turns the *output* on and off. Given these frustrations, it's hard to rate it higher than 3 stars.