Gender Bender (3.5e Equipment)
From D&D Wiki
This girdle appears upon inspection to be a belt of giant strength +2, but when donned the Gender Bender has some unexpected side effects. Instead of granting a Strength bonus, the girdle changes the wearers gender to the opposite sex. This usually has no effect on most gameplay mechanics, but can be quite disturbing. One could be more specific with the girdle's effects, but such things are best left to the imagination. Once is put on, the Gender Bender cannot be removed unless a remove curse spell is cast upon it.