Bones Wheels X99 Formula Timeless Machine V5 Sidecut 99a 56mm Skateboard Wheels are a great choice for skateboarders of all levels. These wheels feature Bones' signature X99 formula, providing a smooth and high-rebound ride. The V5 Sidecut design also offers excellent control for smooth slides. The 99a durometer provides a balance of grip and speed for a variety of surfaces. At 56mm, these wheels are a good size for both street and park skateboarding. This combination of features makes these wheels an ideal choice for anyone looking for a quality set of skateboard wheels.