I have used one at a service station quite regularly. They are okay. I also have a small one you drape across your back or neck which is okay.... nothing is as good as human hands though. These are rotating metal silver balls which go round in a pattern, so not much variation or sensitivity!
Xmas present to my daughter from Amazon not exactly a chair but a massage cushion, neck to feet that you put in a chair or on a sofa or bed with pillows under the top part. Good strong massage with or without heat and easy hand control. Three or four different makes all with good reviews
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