Some self inflicted C.B.T with elastic bands (plus cock rings).
You'll have to forgive the poor quality of this particular clip. It is so old that I seem to have misplaced the original footage (hard to believe I recorded this nearly seven years ago). I do remember being rather sore for quite a while after this session. Not that it bothered me, since I also remember that the orgasm I had at the end of this video was so intense it almost knocked me out. I think I may just have to make a modern follow up to this at some point soon.