Core-flex Active Sitting Ergonomic Executive Chair for Healthy Movement While Sitting w/ Memory Foam Core-flex technology allows the alternating movement of the legs, stimulating the core and back Eliminates the discomfort of a sore bottom because seat pressure alternates from side to side Activates muscles better than standing or sitting on a ball, with no distraction from computer work Your back gets the benefits of walking, without the jarring and distraction The healthiest, most comfortable chair you will ever sit in, made entirely in N. America