Others are correct that this does have a strange installation. It was a bit difficult and took me about fifteen minutes, just to install it; I expected it to take 30 seconds. With that said, it's much better than the lumbar support that comes with the aeron. The lumbar support dug into my back and this can be adjusted a decent amount, but I wish it had more flex. If you want more back support than the aeron chair by itself (but not the back biting lumbar), then get this.$85 is a bit expensive for this though.