Why: First of all it looks good. It can be worn for a dress party, fetish party, usual party, to a club or for a bondage or self-bondage session. And it’s genuine leather. Now let’s focus on (self)bondage.
Despite this “thing” does not have any laces or straps, it’s pretty much inescapable even when unzipped. But your arms must be bound behind your back. Add an ice-padlock between the D-ring and a stationary object and you are trapped! Very simple but very effective selfbondage session. If you pull (even with all your weight) the collar will not dig in your neck, because the ring is in front and will not shift much from its position.
Add the rest (latex, gags, plugs, tights, leotards, catsuits, etc) and do not forget to make and post photos! ;-)
One possible problem: can you zip it up alone?