did not really provide expected results [SEP] my husband had me order this for his back his chiropractor uses one but his is much much higher quality than what you can buy on amazon this one did not live up to expectations though it really did not do the trick my husband had me use it on several vertebrae and could not tell that it helped at all perhaps it is user error i do not know we are just not very happy with the results it does not feel like it is all that adjustable and it does not seem to actually adjust the vertebrae