I love the translation fail. :-D"Welding-free" should be 'soldering-free" or simply "solder-free". In English, welding and soldering are completely different processes. The former ...

I love the translation fail. :-D
"Welding-free" should be 'soldering-free" or simply "solder-free". In English, welding and soldering are completely different processes. The former involves melting the base material and sometimes adding a filler metal. Soldering doesn't involve melting the base material at all and is just adding a filler metal. Soldering is closer to brazing, which usually is higher temperatures using a torch instead of a soldering iron.

That said, mini clips (or sometimes called hook clips) like these are really handy for making temporary connections where alligator clips are simply too large.