YouTube - Justin Kobylka shows the detail and technique of sexing a snake. In this case, a Ball python, both with a probe set, and by popping.
Tips on Buying a Healthy Snake
Ball-Pythons.net - Choosing a ball python at a crowded expo can be an overwhelming task to someone new to the addiction. Members of BP.net offer some excellent advice on choosing a healthy snake that is right for you, as well as making sure you buy from a trusted source.@ Ball-Pythons.net