My mother who is now 80 plus years old has been using your product for I am guessing well over 20 yrs.  I have massaged her many times in the past and she thoroughly enjoys you product as well as myself and recently a friend too, as I have come into possession of it to repair the cord pulling out from the main body which isn't surprising after the many yrs of service and relief it has given my mother.  She has had shoulder surgery in the past and actually manages to use it on a daily basis for muscle relief.  Thanks for a great product.