It is best to choose plastic nails. First, it is not easy to get hurt, because if the base bag is fixed (rubber) and the technical movements such as sliding the base are not mastered well, the impact of the nail on the foot is too great and it is easy to get hurt (there are many examples of fractures); Second, if the bag is movable (sponge), it is easy to be trampled by nails (hehe, take care of public property)! Third, if it is a plastic nail, it can be used in football matches (saving money)!