I've known of this trick, the effect, for years. To me it seemed more of a puzzle than a magical effect-something which may call more attention to the props than to the ability of the magician-or, the 'spirits'. This is where presentation matters-taking this hopefully from a potential bar-bet stunt, to a more compelling phenomenon. Other effects with nuts and bolts point towards a 'force' which shows up and manipulates the objects under clothe ala spirit cabinet. Along these lines, the removal of the ring, may happen unknown to the participant, when it then gets placed beneath a clothe for the magic to THEN takes place.
The trick, as I've seen it, is usually made in India. I'm familiar with some of the questionable quality that can come from the 'land of mysteries', but this prop is actually well done. The price is moderate, the props are examinable, and they are visually attention getting. Gleaming brass, bolt and nuts are large, and heavy. If a woman's ring is used, add to the impossibility factor. How props this borderline clunky could so easily allow such easy passage of a delicate ring, is indeed the mystery. More, it's an easy to carry affair. So, this is one occasion where I may say 'made in Indai, yes-but it's GOOD.'