Advice on Choosing the Right Size and Fit for Chastity Devices

I could use some advice from those more experienced than me.

I own two devices: a (pink) CB-6000 and a (small tube) CellMate. I have a common problem with both of them. No matter how hard I try, the base of my penis ends up outside the cage. I’m “funnel shaped” with plenty of skin at the base. This creates a vicious cycle. Because the penile base is outside the cage, I can still get erect even while caged. Since I am a grower, the tip reaches toward the tube opening and pushes the cage further out. (This also causes unwanted irritation to the penis tip and an uncomfortable pressure on my testicles from behind. Both issues are more pronounced with the CellMate.)

Do I need:

• a longer tube?
• a tighter ring?
• better practice putting it on?

Your penis should touch the entire inner wall of the tube about 95% of the time. A longer tube won't fix this issue.