These wheels have been designed to roll super-smoothly while also providing you with fantastic grip on the floor of the rink.  RollerBones skate wheels are well known in the industry standard for rink, indoor dance, and recreational skating. All 4 colors are offered in either a 57mm or 62mm size (62mm will provides top speeds, while a 57mm will accelerates quicker). All 4 also come in a 98A and the Black & White RollerBones roller skate wheels are offered in a 101A. This is the hardness of the wheels which refers to grip level and a 98A would give you more grip while a 101A would be ideal for sliding.