My only complaint was the odor of the materials when I opened the box and first few uses. It smelled strongly of rubber/oil, like automobile tires. The therapy helps me and I use it at least 5 days of the week.
Works very well on my wife's lower back and on the bottom of my feet. It helps reduce or releave pain from caused by a bulged disc, and from neuropathy.Easy to use, and adjust settings. But, would like to have the battery pack option and be able to move around.Unfortunately, battery is not available at this time.