The format of the stones is the "right", that is like the original. However, the stones are processed much worse: the edges are chamfered and thus less suitable for the purpose, and the surface is rougher. The worst: the accurate processing, the stones are not exactly the same strength, but easily keilförmg. The original stones are so well because they are totally manufactured exactly. This is definitely in the Eichhorn stones not the case. What you should know if you want to save a few euros.