Single ring compared to double ring?

I think a stainless steel cage is definately the way to go. I think weight is a huge factor and may cause the device to sag. Round or oval will depend on how your body adapts. I personally can't wear an oval ring. I find a round ring much more comfortable, but they tend to spin around, especially if your using a padlock. I recommend cutting your chastity teeth by buying several styles of Chinese cages. This will help you figure out the right size and style before spending the big bucks on a custom unit. I've seen a lot of MM devices for sale because the buyers didn't get the measurements right. I have never used a double ring so i can't comment either way, but it will add to the overall weight.

 

I measured multiple times a day for two weeks and still didn't get it right. I ended up sending my Jailbird back a couple times for adjustments. Often times you can find guys on here that will sell a collection of Chinese devices for cheap. A $50 assortment can save you money in the long run.

 

I originally ordered a double base ring with my jailbird that ended up being just a tad too big so I then ordered a smaller single ring and that is what I use now - the single base ring. I also had the gap go smaller too. So now the cage is as snug as can be. I like the smaller single base ring feeling better. I might have a different opinion if the double bass ring with the correct size for me.

 

Call mature metal and get their advice

Like many people I had to make several adjustments to get the fit just right.

FWIW, I personally prefer double oval ring

 

And good luck!

 

Good advice

 

I have a Queens Keep.
Despite ordering the sizing rings, I still ended up sending it back twice before I got the sizing right.
As far as single vs double, the double grips a wider piece of skin, to reduce slipping.
Although they don't really advertise it, they offer a Triple and Quad ring option as well.
After my last adjustment, I now have a Triple Oval basering,
If the skin is dry and hair free, it doesn't move very much at all ...I'm pretty sure the movement I have seen is from clothing pulling on it.

 

MM is great and will also provide a lot of guidance if you inquire with them. They helped me a lot when ordering my Watchful Mistress. I ended up with the oval ring, but cannot speak to how it fits yet as I just ordered it a couple of weeks ago.
As mentioned previously by PeturKitty 58, order some less expensive cages to try out and see what fits well and what doesn't. I found through my trials that I prefer a shorter cage as my size really fluctuates throughout the day. So I took my shortest measurement and subtracted 3/8" from there. Amazon and other places have some really inexpensive options.
My personal experience with base rings, don't go with the ring that is very snug. Go one size larger. The really snug option, once pulled on by the weight of the metal cage may pull on you more than you like. But that is just my experience.
Good luck!!

 

My cage (and ring) kept slipping downwards. Once a partial erection started, it was impossible to stop, and would pull my cage (and ring) further downward, ...with the result being that my cage felt like it would rip my scrotum off until I could will the erection away.

Now, with a snug ring, and cage sized to my flaccid length, the erections can't even get started. If I get turned on, I feel a pressure inside my cage while it tries to get hard, but after a moment of not even getting started, it gives up.

 

...So, Back to your Original question "what is the advantages of a double ring compared to the single?"

Once you feel your ring is already as tight as you can/want to go, adding the extra rings (i.e. double, Triple, Quad) will provide additional grip without further reducing the size. ...but they do add a little extra weight.

As far as Oval vs Round, If they are the same size, then the oval rings average diameter should be the same as the round rings diameter (i.e. they have the same 2 dimensional surface area). I'm pretty sure You can't push any more volume through one than the other.

 

I discussed this issue with Mistress MM.

She told me that if your ring fits correctly, Then while standing naked, comfortable, and flacid in a warm room, you should be able to fit 1 and only 1 finger under the ring up to the 1st knuckle.

In my case at least this turned out to be a very accurate prediction

 

If you are talking the cage itself, tighter may be better. Loose will allow for growth to take place that may make things less comfortable. However, it really depends on how snug the smaller size is.
If this is for your base ring, the process outlined by Alana is accurate and will lead to your ability to naturally swell and shrink without discomfort.