Root Air 110mm Black Pro Scooter Wheels are sold as a 2-pack and are engineered for optimal performance, weighing only 220 grams per wheel with bearings, making them exceptionally light. They feature a hollowcore design, where air is trapped between two sturdy 6061 aluminum plates, ensuring both lightness and remarkable strength. The wheels utilize a high-grade PU (polyurethane) formula, which has become a favorite among professional riders for its speed and durability. These wheels come professionally pre-fitted with super-fast Root Industries Abec 11 Bearings, offering high quality and value. The wheel diameter is 110mm, with a core width and urethane width of 24mm. They are designed with a round wheel profile and include spacers. All Root Industries scooter wheels are rigorously lab-tested and rider-approved, with an 88A PU hardness rating.