Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Spineworx back alignment device

I needed a way to exert pressure to help my spine align properly. In fact I had begun to build my own device and was wondering how to get the right curvature. Then I saw the Spineworx device and decided to try it. My height is 6' 1" and though the fit isn't exact it is close enough. My wife at 5' 6" said it didn't fit her at all. For me the curvature in the lower back portion of the Spineworx device is a little too much and I've found sitting on a thin pillow or folded towel aids comfort. My technique is to extend both arms above the hips and slowly move them in an arc that ends with the arms extended above the head then reverse direction of movement. I do this a few times and roll off after 10 minutes or so. No substitute for a spinal adjustment but might let you extend the time between appointments. I didn't give it 5 stars because it wasn't perfect, but it is certainly worth the money. Suggested improvement: a way to customize the spinal curvature.