Designed with a relatively flat shape, the Fizik Antares R3 Saddle with Kium rails is ideal for cyclists who mix up their riding positions, especially on extended tours and grueling climbs. If you know you fall into Fizik's Chameleon category, which refers to riders with medium spine flexibility, consider the Antares R3. It'll keep you pedaling in comfort towards PR's and new goals while representing a significant upgrade over the stock saddle you've been riding for the past couple of years. As you head out on after-work sunset rides, the Antares' fiberglass-reinforced nylon shell will flex at the point where your thighs meet the saddle, while retaining stiffness throughout the rest of the shell. This design, aptly named WingFlex, limits discomfort without compromising power transfer when you're pedaling hard into a gusty straightaway. The intuitive shell sits atop Fizik's proprietary K:ium rails, created from a titanium alloy that both reduces weight over solid titanium alone and increases stiffness. More affordable than carbon, K:ium boasts a significantly better strength-to-weight ratio than aluminum alloys.