The backrest is fine. it's not the best, but it does theh job. I wanted a back rest because my chair is too deep and I wanted something behind my back. I have gone from no backache to having discomfort in my upper back now. I'm only 5'3, so it may be that I'm too short, but it seems the support around my shoulders is too narrow and forces my shoulders to curl forward. This is causing discomfort. If I hadn't thrown the box away, I would take it back.