Castelli's brand defining Aero Race 5. 1 Full Zip Jersey for men makes a triumphant return this year without giving a second thought towards settling for complacency. The foundational jersey is back with all of the aerodynamic properties it's known for plus an added focus on comfort and longevity. In some manner, Castelli's entire line of impeccably cut apparel has been influenced by the superior fit and function of the Aero Race, and 2016's model promises to live up to and possibly exceed the legacy of its predecessors. Velocity fabric once again takes a large chunk of credit for the jersey's wind cheating properties, as the jersey's front is entirely constituted of the dimpled synthetic. Extremely fast drying, the lightweight fabric helps the jersey achieve its impossibly low claimed weight of 103g, which is about 40g lighter than a standard jersey. The tight weave of Velocity's fibers efficiently works to guide air over the shoulders and reduce drag, and in Castelli's constant quest for improvement this year's updated version of the fabric manages to reportedly save an additional two watts compared to last year's during wind tunnel testing. The back and sleeves of the Aero Race receive a 3D mesh construction rather than Velocity, which breathes remarkably well and features the same dimpled texturing as the front portion of the jersey. This increases the fibers' effective surface area without adding mass, allowing for increased wicking and even faster evaporation. While it might sound contradictory for us to tout the jersey's cool weather capabilities, this quick drying fabric does wonders in warding off a damp chill in spring or fall. Despite the Aero Race's focus on remaining featherweight and aerodynamic, Castelli does include three rear pockets, inlaid in a compressive band that allows them to stay streamlined and as close to your body as possible, even when you have them filled with an assortment of tubes and gels on training rides. A mix of sta..