What's a cock ring?

Happy Monday Everyone (yeah not really, I know)...

Today's post was a question is pretty interesting and was sent in my an anonymous reader:

What exactly is a cock ring, and what does it do?

Basically a cock ring is a sexual device made of either silicone, leather, rubber, or metal that fits snugly around the base of the penis and sometimes the scrotum and creates a trap to enhance sexual pleasure and cause stronger, harder erections.  These can be worn to prolong an erection and also to treat erectile dysfunction.  The come in a variety of designs and sizes, so theres guaranteed to be a cock ring for everyone. 

Some cock rings even have small bullet vibrators attached to the top to serve as clitoral simulators, these are AWESOME... not only will it create a long lasting erection, preventing circulation, but it will stimulate your woman till she begs you to stop... literally...   These cock rings are usually silicone or rubber and are often one size fits all because they are stretchy.  I like these because it enhances the experience for both partners and theres no size dilemma to worry about.  These are also reusable. 

What are your thoughts on this item? Have you tried this? Would you be interested in experimenting with this?