i got mine on ebay
iirc, the name of the store that had the best deals was 'natural remedies" or somethign along those lines.
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it is what dh uses when he needs a chiro vsit(he's had a couple of car wrecks), but we can't get him in there right away, and what i use on my back- especially right before af shows up (i get stomach cramps, but i also get a horrible backache, and it helps a lot.