As I said the device was okay, the strap (extension belt) was not. Confusing picture on booklet instruction. Picture showing the device on top of shoulder and picture showing below shoulder on the upper portion of the arm. I don't really know which one is correct. But, I tried both and the extension belt strap doesn't make sense how to attach it. If it is too tight it doesn't look neat like the one shown on your booklet if its loose it don't do the work.