6373e6b2
As far as I know, you are right; there have been prototypes, but never commercially available.
I would expect at least one technical difficulty though: such plastics can probably not be bent like metal, so how do you adjust it to the wearer? All the wearers here will have experienced that the belt needs to be adjusted numerous times to prevent chafing and pressure points, and to prevent any cheating. Otherwise you would probably need a design that can be adjusted based on a 3D scan of the body, and hope that it turns out right the first time. And even then, you could not adapt it to changes in the body, except probably slight changes in waist size. And would a 3D scan be sufficient? Is the fit of the belt not more dependent on the underlying bone structure than the surface of the skin that would be measured with such a scan?
