IFMAR appropriate, specially-designed 4WD front tires with 12mm interior hex. Perfect fit, and ideal for high-competition race. The wheels are manufactured from versatile material while nonetheless being durable against results. The medial side related to wheel is aerodynamic for optimum performance. Medium hardness. Unique features of the wheel are noticeable from inside: reinforcement ribs to make the tires as stable as you are able to and eliminate deformation. Group of 5 pairs (10 pcs) the price of 4 pairs. An excellent value pack. Fits all XB4