When sleeved baselayers are just too warm, but it isn't quite temperate enough outside to go baselayer-free, the Castelli Prosecco Sleeveless Men's Baselayer strikes the balance to keep your core warm without overheating. Made from Castelli's dual-layer Prosecco fabric, this baselayer boasts hydrophilic properties that usher moisture out and away from your body for quick evaporation so you stay comfortable and dry through intense intervals, endurance miles, and weekend coffee rides.