Castelli Climber's 4.0 Jersey

Racing in the Alps in July is a privilege reserved for only a few, but the products that emerge from it are absolutely amazing for the rest of us. We developed this jersey for hot days in the high mountains, relying on direct feedback from professionals. They wanted a jersey that keeps them cool on hot days without compromising aerodynamics. The Climber’s 4.0 jersey utilizes the same CFD-based seam construction as our Aero Race 7 jersey, but we used the most aerodynamic 3D mesh materials we could find to ensure optimal cooling. These fabrics are also particularly soft and stretchy, providing a comfortable fit that is essential for long days in the mountains. Since this jersey is designed for use under direct sunlight, we ensured that the fabric on the back blocks 90% of UV rays.