Question about Topstar Hard floor castors GAP

They basically fit any chair with a pin diameter of 10 mm. But be careful: Girsberger chairs can also have a pin diameter of 11 mm, like mine, for example. The castors with 10 mm then fit in, but they fall out as soon as the chair is lifted - as in my case. So: measure exactly and only then order and not the other way round as I did.

Pin has length: 25 mm / diameter: 10 mm / distance to centre of snap ring: approx. 5 mm

In my experience, they only fit Topstar