Cock Rings are primarily to slow the flow of blood from the erect penile tissue, thus maintaining an erection for a much longer period of time The purpose of a cock ring is to trap blood inside the penis in order to maintain an erection, or encourage a stronger erection. In order to do this it must be placed at the base of the penis A man may wear an erection ring because he has erectile dysfunction or hyperfunction sorry its sounds so medical but i hope this helps
The restriction from a cock ring creates a similar effect giving the sense of a harder erection, a thicker penis, and a stronger orgasm. The restriction helps him delay ejaculation, remaining hard for an extended period of time and creating a longer sexual experience for both of you.
My BF wears a cock ring pretty much every time we have sex. It makes him totally rock hard and it definitely makes him last longer. The only thing is that he can't cum with it on so he has to pop it off at the right time.
The question was, does it delay ejaculation? Trapping blood in the penis makes it sound like the man can maintain his erection AFTER cumming, or when it would otherwise become flaccid, but does the constriction actually delay ejaculation? Doreigirl's answer implies that it does indeed.