I used this chair for about 2 1/2 months and ended up with pretty severe back, shoulder, and knee pain to the point where we ended up disposing of it in the trash. For reference, I am 5‘2“, weigh about 125 pounds, and I’m pretty active and athletic. It took at least two months of biweekly massage therapy to start to relieve the back and shoulder pain that I experienced that was a direct result of this using this chair. Not recommended. Unnatural seating position not fit for humans.