I have never really checked into the differences between condom size and average penis size but regular condoms are just that, regular. They are for the average sized penis. I haven't been able to put one of these on since I was about 15. After that, it was magnums and now magnum xl. I have friends that have said that they have tried magnums and had to hold on to them with one hand to keep the condom on. Others have said that they kept sliding off. I really didn't say anything but I was kind of laughing inside. One time I was about to have sex with a woman who wanted me to try out one of those glow in the dark condoms. When I was trying to put it on it didn't even fit over the head. She asked innocently, "why did you get the small ones". I looked at her, and she said, "Oh Damn." It was pretty funny, and a big turn on.