Designed with a relatively flat shape, the Fizik Antares R3 Saddle with Kium rails is ideal for the cyclists who mix up their riding positions, especially on extended tours and grueling climbs. Its shape is optimized for what Fizik dubs the Chameleon cyclist, which are riders with medium spine flexibility. The fiberglass infused thermoplastic shell offers lightweight performance with ample stiffness and support. Wingflex technology subtly flexes along the sides to conform to your body without sacrificing the top side's stiff, supportive feel. Moreover, you'll find a Microtex cover, as well as lightweight Kium alloy rails for durability and corrosion resistance.