Cock ring

Does wearing a good quality cock ring through-out the day do anything for girth or length?

I just don’t understand the reason for a cock ring. Do people buy it to have a better erection during sex or can it benefit PEing as well?

A cock ring can make your package stand out more under your clothing. Depending on how tight it is, it can trap a little blood and keep your penis in a plump state. With an erection the ring can help keep blood in and keep it harder longer, even at times when there’s no stimulation (see photos of erotic male dancers, almost all of them have a ring or something tied around their cock and balls). Cock rings cannot make you longer or add to your girth just by wearing them, especially when flaccid. Some will say that keeping it plump helps, but unless there is higher than normal presurre (like during an erection) then there won’t be enough force to make you grow.