I've seen them used sometimes, though. Maybe a good starter one would be one of the black rubber type, just a simple circle type. This type is rather inexpensive compared to some of the more elaborate metal ones.
They are sold in different diameter sizes. A salesperson said to measure the girth size around your hard dick and your balls.

Anyone with some first-hand experience?

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Havn't tried any others since so I can't really offer any suggestions, sorry.

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I have no idea how you are supposed to size those metal ones. My boyfriend bought the biggest one he could find, and we still couldn't get it around his johnson and balls. IF you are going to buy one of those, I would recommend buying a few different sizes. The try the biggest one on, and work your way down to a size that is easy to get on and off.

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The type I have seen, and a few times used (and own) are over the cock only types. Designed to go on when you're soft, pushed down to the base of your cock, and then become quite / very tight when you're hard.

The idea is that they are supposed to prolong erections.

I think they probably do. But that hasn't been a problem with me, so there wasn't that much utility for me. But I could see it for some people. Maybe they do tend to keep you at your peak of hardness though. Wait ... maybe I'm convincing myself to give it another few tries!! <gg>

Type I tried was a couple of different diameter black hard rubber ring jobs. Not very expandable under pressure.

Edited by - dexplorer on Oct 5 2001

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I kind of like using it cause once you are hard, you are REALLY HARD. I mean the veins are bulging and everything. One thing I am not so sure about is when you cum, it stops you from actually ejaculating since it is so tight, but that can be looked at a couple different ways I guess. I find it kind of fun to use now and then, if for no other reason than it looks cool.

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