Castelli builds its #Giro102 Nero Climber's Jersey as a lightweight top for rides with plenty of elevation, like many of the stages in the 2019 Giro. Crafted as a tribute to the now defunct, but at the time hotly contested jersey classification of last place rider, you'll find the Climber to be an asset on those warm summer rides when the road turns up. Castelli also recommends it as a base layer in cooler weather or during rainy rides under a vest or jacket thanks to its minimal moisture absorption. The internal liner keeps things modest and avoids transparency of mesh fabrics. Castelli employs 3D fabric architecture throughout its line, and the Climber features Flusso 3D on the front and shoulders and StradaPro 3D on the back. Flusso is so light that you'll hardly notice it, and Strada Pro is hyper-efficient but has a little more structure to support the three pockets on the back of the jersey. Both wick moisture and breathe exceptionally well to keep you cool and dry. Castelli also engineers the Climber with a built-in bustier lining for comfortable support. AirMesh armbands keep your sleeves in place and provide an aerodynamic fit, and the 3/4-length zipper reduces bulk for an uninterrupted, smooth surface over the jersey's stomach.