2. You need one of these to play a legal game of _________________.
3. What sport are these gentlemen playing?
4. In what athletic competition would you have to contend with this?
5. What is this man telling us?
5a. Or, if you come from New Zealand or Spain or someplace exotic like that, or if you are an effete intellectual, or a member of "the creative class," you may instead identify what sort of contest the following apply to. (Yes, they are in feet, but the shapes are to an international standard.)
Submit your answers in the comments.