2A BUCK-BOOST CONVERTER W/ LED DISPLAY

This is an excellent DC voltage converter, and allows you to cut down on the inventory of DC power supplies. This and a single high current supply, you can derive any voltage you may need. The only lack I see with this item is that there is no attached data sheet to explain operation of both mode buttons. Can anyone help with this?

With the meter facing you, the right key is On/off for the output, not input. As far as Im guessing the converter will still consumer power when "off."

the S key mostly deals with the meter end of things.

Working Mode:
Input voltage mode: [set as default display input voltage], displayed as ".", LED indicator ON, the output is off.
Output voltage mode: Press S1 switch to output voltage mode, display ".", LED indicator off, if turn off the output, display "OFF".
Alternate mode: Press S1 key again, display input/output voltage alternately in 3 seconds, press S1 again switch to "input voltage mode".

Memory Mode:
Long press S1 for 3 seconds for the converter to memorize the current work status and set it to default.
[0]means boot default display input voltage
[1]means boot default display output voltage
[2]means boot default display input/output voltage alternately