So I have recently discovered that I am between the normal ring sizes that come with most all devices. 50mm and my balls will slip back depending on how I sit or sometimes while walking. 45mm cuts off circulation and I start turning blue (not cool). I can't seem to find any websites that really offer custom devices. Anyone know of any that maybe I'm just not pulling up when searching? I prefer the locks that are like you find on a holy trainer (internal) but I like the feel of steel, its the most comfortable that I that I have found based on use of a cb.
you could look into rigid chastity. Just google them. They aren't cheap but extremely well made. They also have terrible customer service from what I hear but they do deliver.
if you have a lathe you can open up the base ring size so you know what would fit perfect for you when bringing your measurements to a custom cage shop i had the exact same issue. 50mm would fall off when doing day to day stuff. 45mm would cause severe issued with night time erections with things turning color. the happy medium for me rests at 47-48mm thankfully i have access to a lathe so i opened it up a little bit at a time and now i can sleep in my device with no problem at all. things will turn a little blue if you are teased while caged, but thats to be expected and will go away when no longer roused.
The chastity devices forum on CM is listed by manufacturer, there you will find all the major custom makers, eg Mature Metal, Male Chastity Now, Steelworxx etc
I'm in the same boat - 50mm is now way too big. I've slowly been printing smaller rings. 46mm just came off the printer tonight, but 44mm is numbingly tight. Do you have a cage where you can adjust the gap? You might be able to get by by making the gap smaller. Someone also suggested wrapping the larger ring in dental floss to lower the diameter.