Premium Material-- Made from sturdy durable polyurethane cast high rebound cushions for increased maneuverability, it provides super grip and stability, perfect for use at home or in the roller disco. The wheel shape keeps the axle ends from scratching the floor. Hightlights-- The wheels are fitted with a built in generator magnet which makes the wheel light up when rolled. As you cruise, these LED wheels light up and cause the exterior color to glow magnificently -- illuminating your every move! With 360 degree visibility and 3-LED lights in each wheel,these light-up wheels to your roller skates is the best way to stand out. Package Included & Light Color-- Pack of 8 light-up wheels replacements, and comes with pre-installed bearings. Each wheel comes with red, blue, and green LED lights that glow automatically when the wheel spins. Note: The data are manual measurement, please allow a 1-3cm error, due to the differences between the light and the display, there will be a certain color difference, the specific received in kind prevail.