Inspired by the towering mountain passes and dizzying switchbacks along Switzerland's awe inspiring Fluela Pass, Castelli's RS Superleggera Jersey was designed as a lightweight, everyday jersey that inherits much of the same technology as Castelli's pro race jerseys. A few functional details added to the Superleggera make it suitable for training, but we can't help but feel that it's a race jersey at heart, ready to propel you up mountain passes and neighborhood climbs not unlike the high speed car it happens to share a name with. Castelli strove to make this jersey as light as possible while giving it enough versatility to avoid strictly being classified as a climber's jersey. To do this, Castelli constructed the body and sleeves with 50gm2 Futura fabric, a barely there, stretchy synthetic that adeptly draws moisture away from your body as you ride. We were also pleasantly surprised to find that it has a strikingly soft touch. A compression panel of Castelli's Stretch Woven fabric added to the bottom half of the jersey allows the Superleggera to follow your movements in the saddle without constriction. 3 D mesh fabric inserts at the back and side panels further add to the jersey's breathability, facilitating airflow as you tackle steep, slow ascents when the breeze stands still. In pro race kit, details like a zippered security pocket, top zipper protection, and gripper elastic around the waist aren't essential, but Castelli adds these finishing touches to the Superleggera for comfort and convenience during everyday rides. No sew seaming on the waist and sleeves creates clean, lie flat cuffs that won't pinch or chafe, and the joints are bonded and reinforced to ensure they won't unravel after a single wash. Despite these training details, the Superleggera is still a race cut jersey, so expect the same tailored, smaller than average fit you would from other Castelli gear. It's also got the Italian firm's signature in saddle design: a tighter fit across the ...