it's called a "Band Elastrator" and you can get it at farm/rural supply shops. it's for castrating farm animals ("gelding" them). basically, it is a device that stretches a very tight, very small, very thick rubber band wide enough to fit a pair of balls (or a clit?) through, then the thing is let go and it crushes the testicular vessels and eventually the balls get gangrenous and fall off. it looked like fun, but one should probably remember to be careful, too. it could be hard to get off before you're hurt.

--annie d