Fi'zi:k Antares R3 K:ium Saddle. The Fi'zi:k Antares R3 K:ium Saddle definitely stands out from the crowd in the realm of high performance saddles. The Antares is made for riders who have average flexibility what Fi'zi:k considers a Chameleon in their Spine Concept fit system, but still like to move around on the saddle. It's a long, thinner saddle that helps you get into different positions depending on how you're riding, and the long, thin nose helps eliminate leg chafing the Wing Flex shell flexes downward where the inner thigh contacts the saddle, allowing more efficient pedaling and full range of motion. Additionally, the K:ium alloy rails are lighter than titanium, yet plenty stiff so they won't deform under power.