They are their own category of energy tools. The link @TheBlackEmperor provided is for the website of the man who (re)discovered tensor ring technology in modern times, Slim Spurling. But after he died, tensor ring tech was perfected by a brother & sister team, Brian Besco the master craftsman and Brenda Schnose the channeler. Their website is:
As a metaphor, you can think of Slim Spurling’s tensor rings, which he called Light-Life rings, as being like subliminals and Brian Besco’s tensor rings as being like energetically-programmed audios. Both can help people, but the latter is far ahead in sophistication & technology, not to mention MUCH more effective.
Take a look at their website and pay attention to the pictures. The energy of the rings will come through their photos, so you can get a feel for them if you’re energy sensitive enough. If any of them feel intriguing, or if you feel your attention being drawn to them, then that’s a sign that your system wants the energy and you should buy one.
That’s what happened to me when I first heard about these.