Alpha Ros Light Limited Edition Jacket

Although "light" is in the title of Castelli's Alpha Ros Light Limited Edition Jacket, don't let that fool you into thinking it isn't versatile. Far from it, after all, RoS stands for Rain or Shine, meaning you'll get wind- and water protection when you need it but it also breathes so well and manages moisture you won't hesitate to grab it on a bluebird day as well. Depending on the conditions and your own personal comfort range, we feel the jacket is true to Castelli's suggested temperature range of 46 - 59 degrees Fahrenheit which just so happens to be where we find the bulk of our shoulder season rides. If it's drizzling, windy and high 50's? No problem, it's quite comfortable. Likewise, a sunny, calm day in the mid-40s is fine too and the addition of a thermal baselayer can get you down to the low-40s.

Keeping the elements out is Gore's Windstopper 150 membrane on the front and sleeves. Where the magic really happens is on the back where Castelli uses its Nano Flex Xtra Dry, a thermal material with a DWR treatment that dumps excess heat, improves breathability, and maintains a water-resistant surface across the entire jacket. It's probably the most water resistant fabric this side of something with a membrane and its ventilation is unmatched.

The Windstopper layer is separated from a ProSecco Strada inner liner across the front panel, letting you unzip the protective shell while leaving the thermal layer intact, allowing moderate airflow on extended climbs without exposing your bare chest to a frigid, wintery blast. Skiers and alpinists use Windstopper indiscriminately: their goal is to stay warm and dry at all costs. Cyclists' needs, on the other hand, change over the course of a ride depending on intensity, climbing, descending, etc., so we need the protection to change with us in real time. The Alpha solves that problem.

  • Castelli's most versatile jacket for training and racing
  • Windstopper 150 membrane blocks wind and water without stifling
  • Rear thermal panel breathes but keeps the rain at bay
  • Separate thermal mid-layer provides targeted warmth
  • Race fit eliminates flapping material during tempo base miles
  • Maintains breathability to manage moisture during hard efforts
  • Raw-cut hem and cuffs reduce bulk and maintain coverage
  • Limited edition colorway looks sharp on the open roads
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