Arione 00: a saddle of two halves, lightness and flexibility. Arione 00 rapresents the pinnacle of innovation and design within the Arione collection of professional racing saddles. It's light, flexible and agile, enabling you to perform at your optimum. The speed of light in a saddle, designed for pros, and raced by pros. Spine Concept. Spine Concept is the fi'zi:k guideline to the right saddle choice. It realizes that cyclists have varying degrees of flexibility and human flexibility affects riding behavior when cycling in a high performance position.