[EricH]

All field elements are provided by FIRST at the events. This includes the Trident, the balls, the bumps, the towers, the practice field and its equipment if there is one, you get the picture.

You don't need to bring one, but if your HP is going to be spending time on the practice field, you may want one. As it is not a robot part, it may or may not be included in the Withholding Allowance (it could be made into a lot of spacers...)