David, it'sa contraption that completely encircles the arrow shaft, holding it in the middle with powerful magnets. The arrow shaft is virtually floating in mid-air. I believe you have to use a special insert for it to work correctly. Of course, it's got its loyal followers as well as its detractors already.

If I'm not mistaken, your buddy Len played with one extensively at the ATA show and offered the inventor some feedback on ways to improve it.