Terrible design. The metal brackets on the legs (zoom in) that attach into the base of the chair are angled. This seems like it would add a 'spring-like' function, but this poor design going into a PLASTIC hole means that it will quickly become stripped and break.  The chair has been used for only 2 months here and there and it is broken. The angle of the metal brackets act like the claw of a hammer and pulls the screw out of the plastic... which isn't held in by anything.

Looks nice, but it is a Complete waste of money .The person sitting on it weighed 155 Lbs.