this device came with a 90 day warranty, so after 2 months I hadn't received any results that were of benefit to my back, may be it works for some people, the problem came when, following their return instructions, I contacted customer service and get a RMA number(return merchandise authorization) and placed it on the return address just like they requested. They warn that without that number they would NOT accept the return.
Guess what? I followed these instructions, paid an additional $17.00 for postage and insurance AND they still REFUSED the shipment!!
SO I advise OTHERS to be very careful with these crooks!