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Castelli Alpha RoS Jacket


Castelli Alpha RoS - Rain or Shine engineering provides insulation and breathability for cold dry conditions with great protection during wet rides and a superb fit all built into a full specification winter cycling jacket... Read more

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SKU: CS175023412


Castelli Alpha RoS - Rain or Shine engineering provides insulation and breathability for cold dry conditions with great protection during wet rides and a superb fit all built into a full specification winter cycling jacket.

The goal when Castelli started work on the Alpha Jacket was to create a winter jacket that is good as it can be for cold days. A jacket offering supreme comfort and breathability, a jacket that can adapt to changing temperatures and conditions.

Additionally, they wanted a jacket that if you did get caught in a heavy shower or the day turned for the worst, you would make it back home warm and mainly dry.

To achieve this Castelli started with the excellent Gore Windstopper 150 fabric offering a barrier against the wind and rain, then added a fleece lining with its own independent front zipper allowing you to control frontal airflow. A large covered vent in the back works alongside this to allow through-flow of air in milder drier conditions.

While not being a fully waterproof jacket the Alpha use selective seam sealing, double seams and a partially covered front zipper to keep the worst of the weather out.

Key Features
  • Gore® Windstopper® 150 fabric is windproof highly breathable and offers great protection from rain and spray
  • Seam sealing on the shoulders with a reduced seam main body and double stitching work to keep you dry in all but the worst conditions
  • Dual layer Alpha construction separates insulation and protection to create better ventilation, moisture evaporation and breathability
  • Articulated Collar for a better fit
  • Part covered waterproof YKK® Vislon zipper lays flat and slides easily
  • Raw edge waist follows the body contours, lays flat and is low bulk
  • Raw edge wrists create a perfect interface with Castelli gloves
  • The stretch fabrics combined with the latest advanced patterning creates a close fit on a wide range of body types
  • Back ventilation for greater comfort
  • Castelli silicone text gripper at waist keeps the jacket from riding up
  • Front zippered key pocket - with waterproof zip
  • Three large open rear pockets with laser cut reflective drainage patterning
  • Sizes Men's S-3XL
  • Weight 515 g (Size L )
  • Castelli Comfort Range -5˚ to 10˚C


ABOUT Castelli

Castelli Cycling is the most innovative, stylish and prestigious cycling clothier in the world. Decades of pro cycling development and a passion for perfection in materials, cut and performance has seen the brand reinvent cycle wear time after time. From the first Lycra shorts to sublimated printing, the game-changing Gabba and aerodynamic apparel, Castelli continues to set a path that others can only follow while maintaining generations of Italian heritage. Read more about Castelli.


Founded by real cycling enthusiasts in 2004, our passion for elite performance runs through everything we do at Saddleback. Our team of dedicated roadies, mountain bikers and triathletes practice what we preach to bring you the finest cycling products and a superior service to match. We're the official UK home of 3T, Castelli, Chris King, ENVE, Intense, Peaty's, PUSH, Sidi, Silca, Stages, Troy Lee Designs and Wolf Tooth.

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