Difficulties with wearing a device? discussion

I’ve spent years hunting for the right tube dimensions. I create tubes in different sizes to test whether they hold on. Over time, the glans tends to retract into the device and it invariably slides off. It’s tricky to explain: essentially, the head slips inside and continues inward… Picture peeling a sock back over your foot; that rolling motion is how my skin permits the penis to exit. I have what you’d call a “loose” circumcision, plus my shaft shrinks significantly when flaccid.

I’ve tested fairly snug tubes too—so tight that urination becomes difficult—and yet they still pop out. This makes me wonder: perhaps the tubes are just too constricted and the pressure is forcing them off? Could switching to a slightly looser fit help?

Any insights or suggestions would be welcome. I do own a PA, but it’s not very useful right now because until I locate a tube that stays put, the piercing endures excessive strain.