I'm interested to know that as well.
I have some that I ordered from Fireboy Underwear. They offer what they call a 3D pouch, so the pouch is anatomically shaped for your balls, then tapers for your cock.. They offer it with and without a built in band as a cock ring. It does help keep your balls from being squeezed back out of the pouch. Or you can wear it with your own ring around your cock and balls.
I took my pictures without a cock ring and struggled to keep the pouch...That was already too large....filled.
Either way, they offer the pouches in different sizes....Don't be greedy, their measurements are accurate. I certainly overestimated my ability to fill the pouch, and I wasn't pleased with the results. They will remind you the material is very stretchy, and stretching some is a good thing.
Looking at my pics, another thing is that the "pouch" is very out front. At my age, I tend to be a little more discreet. You aren't going to be 'dangling' a lot wearing these.
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