I don't have much to say; they do their job quite a bit better than the chair's stock ones I used them with. Also, it's a plus that they don't seem to scratch the wooden floor.

The purpose of purchasing these specific ones was to protect a wooden floor (parquet), which did not happen. The wheels that the chair had when it was bought (not some expensive ones) were very good and did not mark the floor, but they broke due to extensive use and normal wear. While these ones seemed very promising, unfortunately, they were a disappointment.
I suppose that on another type of floor (not wooden) they would do their job just fine.

They do their job, I put them on an old office chair of mine where the wheels were made of cheap plastic and broke, these are by far better, clear difference.

They were installed in a set of 5, on a work chair from the company SEDIA, as the price difference with the "genuine" ones was significant. Installation time was 5 minutes, perfect fit. I believe that if they are regularly cleaned, they will last a long time. Overall, they are value for money, compared to "simpler" and cheaper completely plastic ones. The use is professional and daily on laminate flooring, no problems so far (2 months +).