I needed a bit longer mono cable, mini to normal jack and ordered this. It did not work for me because stereo channels were soldered together. That means if you plug it into mini mono plug, the signal will be grounded. So, no luck.
I am even not sure what what would be the application for this cable. Usually you do not sum left and right just by connecting them together... at least the catalog should clearly state what is connected to what.
Anyway, I am a bit of a handyman, so I got my soldering iron and ventured into modifying the cable. What I needed to do is to unsolder the middle terminal from signal and solder it to the ground. Unfortunately, the mini jack plastic is of bad quality so the insulation melted, and the shaft became wobbly. Scrapped it as unusable.