The thread in feet design is defective, making my chairs unusable after just a month. If you thread a foot out a bit to level the chair, it ends up dislodging the press fit female threads in the leg. Once this happens, if the foot is ever fully unthreaded, it is impossible to get it back on, as the press fit threads are simply pushed up into the leg. So, now my new chair has no foot, just a hard metal edge.