Hi,
I went to the backtivator link you provided, but I couldn't order it, it said you had to be a doctor
however, I did find it here:
http://www.necksolutions.com/backtivator.html I ordered two of them,
one for my chair at work and one for my car.... I am really impressed, they work great to reduce the stiffness in my lower back. I was surprised considering how small they are.
T.