Quality but useless accessories
This cable works perfectly, charging my Samsung Galaxy S21 in just over an hour, which is perfect (note that it does this with the compatible power supply, also from Belklin).
What's more, the cable seems to be of high quality.
The only drawback to this quality is the weight of the cable: if I leave it dangling, the cable tends to move away from the connector on my Samsung and stop charging its battery. But if I leave it flat, no problem.
Finally, as an accessory, there's a little magnet to stick on the cable while charging, but I don't find it useful. Or rather, I'd rather make sure I place my cable myself to prevent it from moving than have to magnetise it every time I charge.
Especially as, once it's stuck in place, the magnet is supposed to stay where it is, but I don't always charge my phone in the same place.