I received this chair last Thursday, and by Monday it was already not functioning after only approximately 8 uses. I bought this chair as a gift for my father, who has a shoulder problem. When the technician came, he said the circuit board was broken and that we need to wait for parts from China, with no estimated date for arrival. This product has significant quality issues, and the warranty is only for one year. I have no idea when my chair will be fully repaired. Very disappointing experience. DO NOT BUY!!!