I bought this off Amazon. As others state, this thing is almost unusable by normal height people. I'm 6' and the lowest setting is WAY too high. Several inches higher than my old chair. The armrests also don't go low enough. They hit my desk. The arms can maybe be lowered some by adding spacers and longer bolts to the bottom of the seat. As for height, I kind of fixed it, or at least tolerable, by using these smaller diameter wheels off amazon. The new wheels actually roll better and the blue color matches by blue/grey color scheme. Much better.
https://www.amazon.com/gp/product/B01AIDB5AM/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B01AIDB5AM/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1