Spiral, not ring.

Short and sweet:
The rings I got, if you want to use them as key rings, scrap.
After you have drawn up a key, you have a spiral that no longer ring, because the steel bends easily just plastic and not springy, elastic returns.

They seem to have optimized away the hardships of the Rings, or to have taken simple structural steel?
Who buys cheap, buys twice.
I am very upset about the lack of quality.
(I had even ordered the 15mm version: That's OK.)

Addendum:
Did the seller "ge-gra pattern GmbH" directly written:
Received no response.