This is a pack of ten XRAY 4WD Aerodisk Front Wheels with 12mm Hexes. Specially-designed 4WD front wheels with 12mm internal hex. Perfect fit, and perfect for competition. The wheels are made from flexible material while still being durable against impacts. The side of the wheel is aerodynamic for maximum performance. Reinforcement ribs to make the wheels as stable as possible and eliminate deformation.