What Our Gearhead Experts Are Saying:"This cap is perfect for hot days on the bike. The mesh fabric keeps me cool, and it fits snugly under my helmet without adding bulk."The Castelli Climber’s A/C Cap is designed to help us beat the heat on steep, sunny climbs. Crafted with performance mesh fabric, this cap maximizes airflow and wicks moisture away, keeping us cool and comfortable during the hottest rides. The lightweight design and snug elastic fit ensure a seamless fit under our helmet, while the short brim provides just the right amount of sun protection. With stylish graphics to complete the look, this cap is an essential addition to our summer cycling kit.