Class-leading aerodynamics paired with all-day comfort.This jersey in engineered to save you watts while managing moisture and providing comfort for the longest rides.FEATURES:-CFD-based fabric placement and seam construction Castelli engineered Air_O Strecth fabric for breathabiity, comfort and stretch Engineered for aero efficiency at 30 to 55 km/h To be paired with Bolero SS base layer for added aero gains, or without base layer for hot days Airflow shoulder construction Elbow-length stretch sleeves with raw-cut edge Elastic around waist to keep jersey in place and support pockets YKK® Vislon® zipper Contains bluesign® certified fabrics.