I just ordered from Dietmar, but I’m now doubting my tube size measurement. I found a household item with an exact 31.5mm diameter and naturally had to try shoving my junk inside. It was quite the struggle. I used the stocking trick to get it in, and looking at it from the other side revealed significant compression around the tip, which looked problematic. O-ring testing has shown me that a 1.25” ring overnight behind the head is no issue for me, but now I wonder if this is truly the right size for the head itself.
Should I measure the tube to match the shaft’s circumference and diameter or focus on the head? In my case, these differ quite a bit even when flaccid (99mm versus 110mm).
Re-reading before posting, I think I’ll email Dietmar and choose the larger size (35mm ID). Otherwise, I’d have to rely on the stocking trick just to get in—which would likely render the urethral insert useless.