It is an "active sitting" chair. Sitting in a normal chair hurts my back and neck because I have terrible posture. This wobbly chair forces me to sit upright and provides some freedom of movement. It also allegedly works your core.
Sure, come say hi and try it out.
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I haven't sat in a normal office chair for over 9 years and couldn't make the adjustment to it when I started working here. It was time to make the investment.