I liked this little adapter so much that I bought another one.
It is resistant (i.e. you can step on top of it with no worries).
It has good ergonomics. This makes it easier to insert/remove cables. The rubber around it does not slip much. It has a nice grip.
It is stereo, but works with mono cables as well.
I could not detect any noise while using it. I have used (just for testing purposes) two of them to create a bigger apparently without issues. I guess the gold-plated contacts help.
The cables do feel secure but it does not have a locking mechanism.
If a locking mechanism is needed, the apparently even more resistant Neutrik NA3 JJ might be a better option. Neutrik is Neutrik. However, at the time I write this review, the Neutrik NA3 JJ adapter costs more than the double than this one.
In conclusion, I found that it has a very good price-quality ration for my current needs.
Not as bad as some cheaper versions, not as good as the Neutrik one.
To finish I transcribe here the description written in the back of the package. At the time of writing it has more information that the description given by Thomann.
"The Planet Waves 1/4" (6.35mm) stereo female coupler is ergonomically designed with a durable polymer overmold for extra protection and easy gripping. Planet Waves adapers are fully shielded and have 24-karat gold-plated contacts for maximum conductivity and corrosion resistance."
Maybe I will buy a third one in the future :)