Scam products, scam site
You can safely consider this a scam site.
Their chairs are terrible.
Ergonomics wise you are better off standing on your knees on the floor.
Quality-wise? Unacceptable. After one year the back support and the head pillow will become unusable. It will also start to crack and make noise with every movement and it will also become really unstable
After two years every single seam of the base will start ripping apart.
Even if you for some reason you can find this chair comfortable you can forget about any kind of support. They usually ignore all the emails, calls, and messages and when you are able to reach them out will ignore any kind of legislation and avoid fulfilling their warranty obligations: if they keep responding at this point they will blame everything on "wear and tear".