It does what it's supposed to
Years ago I had to have one of these just to hold down a job where I had to sit all day.  If I didn't have this, my spine would hurt excruciatingly.  That one eventually broke so when I had a problem with my hip I bought one so I could sit and make lampwork beads for a long time.  I am positive that it keeps your spine aligned when you are sitting on it.  I think it is invaluable.  I was so happy to see I could purchase one of these on Amazon!
Rating: 5 stars