The wheels are IFMAR standardized aided by the wheel hex offset. The tires function countersunk center area that allows the wheel nut to stay deeper in wheel. The tires are perfect for high-competition race. They function interior reinforcement ribs to deliver security and resist deformation, yet these are typically made from a flexible product to supply durability and withstand effects. The side of wheel is aerodynamic for maximum performance. The tires were made to offer maximum traction. The wheels function a 12mm interior hex. Pair of 10 (5 pair)