I regularly get mail from people with basic chastity questions. This seems like a good time to share some of my updated knowledge that might be of help to people just getting started.
Penis Shrink
This is a persistent myth that keeps getting debated on forums and in my mail box. I’ve been wearing a chastity device over four years. My penis is exactly the same size it was before we started this in 2013. After puberty, your penis is pretty much the size it’s going to be for the rest of your life. Squishing your flaccid penis into a short chastity device will not change its size.
Similarly, some guys swear their scrotum shrinks when they wear a device from the pressure and stretch of the base ring and the weight of the device. There’s no evidence of that happening either. It’s true that the stretch will allow wearing a smaller base ring. This has less to do with physiology than it does with getting used to wearing a device. More about base rings later.
Cage Size
This is a subject that is near and dear to guys involved with enforced male chastity. Over the years, I’ve learned a lot from direct experience wearing devices. The general advice from Mature Metal (they make the Jail Bird device that I wear) is that device should touch the sides and top of your penis at all times. It should fit, “like a glove”.
That’s good advice. But measuring is truly tricky. First thing, I now know that there is no such thing as too short for a cage. The flaccid penis compresses painlessly to a surprisingly short length. My best advice is to lay the head of your penis on a ruler and measure its length, from the tip of your urethra to just under the glans. That’s probably a good size for your cage. Bear in mind that the actual device adds the the diameter of the base ring as well as the gap between the cage and your scrotum. So the real length will be at least another quarter inch longer. Sound crazy? It’s not. It works.
The diameter of the cage should be about 1/4-inch narrower than the measured diameter of your soft penis. This is easy to measure. Just lay your cock across a ruler. Hold it so it doesn’t flatten. There you go! If you have a caliper, that’s even better. My penis diameter is 1-1/2 inches (soft) and my cage is 1-1/4 inches in diameter. It fits perfectly. It’s important to be sure your cage isn’t too narrow. A lot of the Chinese devices have cage diameters of one inch. That’s too narrow for most guys.
I don’t think you can get a cage that is too short. Just be sure the diameter is correct for you.
Base Ring
This is the most debated size issue in chastity device purchasing. Most of what you read insists that you wear the smallest size possible. The reason is that it is more secure. I don’t get that at all. You’re wearing the device because you want to. No ball capture device is inescapable, even with a piercing. Security isn’t really a big issue at all.
The most important attribute a chastity device can have is comfort. If you can’t comfortably wear it 24/7, then it isn’t going to work out for you. The base ring is the most important component that affects your comfort.
The only way to figure out what size is best is to get a set of sizing rings. Mature Metal sells one (link here) at a reasonable price. Finding your size isn’t hard at all. I started with a 2-inch ring. I had it on an inexpensive Chinese device (dhgate.com). I didn’t worry about the cage itself. It was way too big. When I wore the device with the 2-inch ring, a ball kept slipping out. Clearly it was too big. Then I tried the device with a 1-3/4 inch ring. Nothing slipped out and it was comfortable to wear. Next, I tried 1-1/2 inches. That hurt after a while.
Last year, I decided to experiment further. I had Mature Metal make me 1-5/8 and 1-11/16 inch rings. I was surprised that neither were comfortable.
My suggestion is to always wear a base ring that doesn’t hurt. If you have to use some sort of lube to be comfortable, then the ring is almost certainly too small. You need friction between your body and the ring to help with erections (more about that later). But you shouldn’t have pain when you wear the ring dry.
Erections
A chastity device is supposed to prevent erections. Your penis shouldn’t grow when you are aroused and wearing the device. That doesn’t mean there won’t be changes when you try to get hard. If you have a properly fitting device, when you are aroused, you will feel (and see) that the tissue behind the base ring is hard. This isn’t the result of the chastity device moving or failing. There is erectile tissue behind the base of your penis. It will become hard when you are aroused.
The shaft of your penis shouldn’t grow at all. It should expand and push on the top and walls of your chastity device. When Mrs. Lion takes my device off, she will sometimes see “grill marks” where the bars on the top of the cage temporarily dents my penis. That’s evidence things are working correctly. It’s that pressure on the sides and top of the device that help keep it in place.
Some people report that the cage and base ring are pushed out over the scrotum and hurt the balls due to this motion. This is not the desired effect of wearing a device. Using lube under the base ring encourages this sort of problem. Too large a base ring can also be to blame. However, there may be another explanation for this.
When some men get aroused, the scrotum shrinks, pulling the balls tight against the body. This gets them out of harm’s way during sex. The scrotum has thin muscle under the skin. This muscle pulls the balls back. It helps regulate the temperature of the balls. They need to be cooler than body temperature for optimum sperm production.
Anyway, some guys have strong muscle there. When they are wearing a device and try to get hard, the scrotum pulls the testicles back and the base ring stops their progress. This can hurt. If this is the case, there is nothing changing base ring size will do to help. Just don’t get hard.
Shopping
Most guys don’t want to spend too much money on a chastity device when they are just starting out. There is a wide variety of inexpensive devices available. Maybe you can find one just the right size for you. It’s very unlikely, but perhaps you can find one comfortable enough to wear. If you plan to wear one long term, you will almost certainly want to get a custom device. These devices run about $400 USD. They’re worth every penny.
Devices are made in a variety of materials. I’ve tried them all. The worst for me is silicone. These devices are very insecure, hot to wear, and very difficult to fasten and lock. There are hard plastic devices like the CB6000. They don’t work for me because they don’t offer a short enough cage size. They also tend to split over time and the base ring has too much friction with my body. Many guys use lube to compensate for that. I don’t think that is a very good idea at all.
Recently, some people are offering 3D-printed devices made of medical grade nylon. I have one. I had to sand the device before wearing it. It felt like sandpaper the way I received it. It works very well and if you are willing to sand and polish a bit, it’s an inexpensive way to get a custom device. I paid less than $300 USD for it. Nylon works better against my skin. Unlike acrylic that is used for the CB600, nylon is almost like steel in the way it works against my skin.
In my opinion, the best way to go is with surgical grade stainless steel. This material is secure and comfortable to wear. The Chinese steel devices claim to be surgical grade stainless, but who knows? Don’t buy a device that is chromes plated. The plating is quickly eaten away by your body secretions.
I think the best way to go is with a custom Mature Metal Jail Bird. Most of the people who have been caged for a while say the Jail Bird is the most comfortable and easiest-to-keep-clean device available. It’s an open cage design. It works perfectly for me.
If you aren’t ready to spend several hundred dollars, you can get workable cages from dhgate (this one was surprisingly comfortable). Look for stainless steel. The base ring should be solid (not hinged. The hinges hurt!). Watch out for the cage diameter. Too narrow or wide cages are uncomfortable and difficult to use when peeing. All of the devices you find on Amazon are available for much less on dhgate.
Hopefully, this information will be useful for you and your keyholder.