Chair was assembled for the most part, the assembly was easy. Only with the attachment of the armrests, which are far too low, I had problems. Assembly instructions of the armrests was missing. Now after one day use the tilt function captures the squeak on. Tried to get at evil with a few drops of WD-40, to no avail. The armrests are processed unclean and have burrs. The only good thing: you sit comfortably upright.
Conclusion: I'm going to send him back, but buy in a shop which you can test it out!