Just finished the assembly of SIHOO M-18 Office chair. I am 65 years old, so I worked slowly, but still less than a hour. User manual is in color, and easy to follow. The base is chrome plated steel, with clever plastic inserts to help prevent creaking. All bolts have plastic applied to keep from coming loose and extra hardware included in case you loose one. A Tee handled tool was included. The assembled chair is quiet and working properly.