Castelli Climber's 4.0 Jersey Discover excellence in performance with the Castelli Climber's 4.0 jersey, designed to maximize your aerodynamic efficiency and cooling during the most demanding climbs. Light and breathable, this jacket is your perfect ally to face high temperatures. Material: Bluesign® certified fabrics for a lower environmental impact. Knitting technology: Flusso 3D on the front, StradaPro 3D on the back. Breathability: StradaPro 3D back for optimal ventilation. Water resistance: N/A. Fit: Race slim fit, elastic sleeves, elastic waist. Weight: 164 g, ideal for temperatures from 22°C to 40°C. Specific technology: CFD-based fabric distribution, Airflow shoulder structure, YKK® Vislon® zipper.