These are replacement rubber caps for the Rangs Balance Hopping. This is a set of two new items. *The replacement caps are designed to be sufficiently secure even without screwing them in. If even one of the circular patterns on the bottom is chipped or worn away and no longer circular, please replace it. If you continue to ride until all the patterns disappear, the metal inside will become exposed, so replace them promptly. - Material: Rubber - Shape: Cylindrical - Internal structure: Contains metal parts