cock rings

o.o i wanna know the dangers too

as long as you don't use them all of the time.....the looser the material and/or diameter of the cock ring the better. The fit has to only be a little tight. I have a 1 inch cock ring and I'm 1 1/2 inches across so its a good snug fit without being too tight. Don't use it for hours at a time. I would not try metal or anything fixed. Stay with rubber

Cock rings are not generally considered dangerous or harmful as long as they are used correctly and safely. Most importantly, they should not be kept in place for more than half an hour. When a man is erect, there are tubes that are engorged with blood. But, this blood does not carry oxygen to the tissues of the penis. Having an unwavering erection can actually cut off blood supply to the penis. If left on for too long, you can even burst blood vessels, causing bruising, swelling, and sometimes even vascular damage.
For these reasons, specialists often recommend that if you wish to experiment, use a ring made of fabric or rubber -- something that can be cut in an emergency.