It's now 3 weeks since I notified Mr.Sornik that the material I bought from him is unusable because of the reason and the bad quality of steel used for the different blocking pieces which for material of daily use is inadmissible, but since then I don't have any more news from this gentleman, neither an advice nor a solution, nothing.
low grade steel threaded metal inserts
Oh, that's for sure not German quality.😁