This device, named in keeping with long standing tradition, is used for male constraint and adornment.
It consists of a series of nickel-plated steel rings connected by a leather strap. The first, largest ring goes over the cock and balls, and the cock alone goes into the other rings.
The rings get progressively smaller, confining the penis.
On this 7-Ring version, the first ring is 2" in diameter. The second and third rings are 1¾", the next three are 1½", and the last one is 1¼". The entire length is about 4".