While this discussion is about nozzles I'll change the subject a bit to colon tubes.
It has often been said, most colon tubes just curl up in the rectum and don't go very far. That's probably the case most of the time. In my younger days I did a lot of experimenting and learned how to push the tube out of the rectum and about as far as the sigmoid.
A friend, who used to go to auctions as nursing homes in Maine were shutting down would purchase all the enema equipment he could find. He got several 38fr tubes, we had been having a discussion about colon tube insertion, and he said try this and gave me one. This tube had just the right size and flexibility, it was a bit stiffer than any tubes I had to that point, just the right flexibility to go past the sigmoid and into the transverse colon. I used it with a couple of partners, and it worked for them, too. Probably as close to the cecum as you could get, not uncomfortable, a very erotic feeling. We had palpitated each other, and, we would detect just where the tip was. And, I always enjoyed being filled from the top down.
Age got to that hose, sadly, a long time ago. It was probably quite old when it was given to me. Over the years I met two "nurses" that could get even the softer tubes past the sigmoid, Mildred Burgess in Boston and Valarie at Grand Dames in Los Angeles. Then nothing, no success.
Now there are the Silicone Nozzles, I think the lager diameter helps, and with the larger diameter it is very easy to feel and detect how deep they are.
So how many others have had a truly deep colon tube experience, pre or post silicone nozzles and...
Which diameter and stiffness of those nozzles seems to work best? What is the optimum length?