The Inline Skate Wheels are a set of 8 wheels, that light up when in use. A fun and creative way to make yourself visible while skating at night. The Wheels uses technology so they do not need to be charger and do not require batteries. The Inline Skate Wheels light up based on the movement of the wheels, a great gift for kids or fun adults. Users can remove the core of the wheel and the lights will not light up. Prefect for any pair of inline skates, with a 88a durometer/hardness they make for a smooth ride.