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Castelli Alpha Ros Jacket - Light Black/Black


And extraordinarily versatile, special cycling jacket - it will keep you dry in all but monsoon conditions and warm in any temperature over freezing. You'll struggle to find a better one-stop shop for your rides.

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When Castelli started work on the Alpha RoS W Jacket, the aim was to create a winter jacket that is effective as possible for cold days: a cycling jacket combining unsurpassed comfort and breathability; a cycling jacket that can adapt to changing temperatures and conditions.

More than that, they wanted to make a cycling jacket that would get you back home as warm and dry as exceptionally breathable material will allow. Whilst this prevents it from describing itself as fully 'waterproof', in practice - short of prolonged monsoon conditions - it's as near waterproof as you'll find. The Alpha RoS jacket is designed for serious winter riding in all conditions - as close to a one-stop shop solution as modern fabrics and technologies allow.

So how have Castelli managed it? Through new fabrics with extreme breathability and improved water repellency - plus clever design details to keep the water out yet provide ample breathability and ventilation. 

The Rain or Shine (RoS - see?!) system utilises Gore-Tex Infinium 150 fabric to achieve all this. It also incorporates Castelli's Alpha construction - separating the wind/water protection layer from the insulating layer. This means better control of your ventilation and better moisture evaporation.

The result is a unique jacket that allows you to ride from freezing, dry conditions right through to wet and much milder conditions. 

The stretch fabrics with advanced fitting make for an excellent close cut that still allows for a reassuringly wide range of body types. The raw-edge waist lies flat and moves with you - this combined with the Castelli silicone text gripper at waist keeps the jacket from riding up.

A triple rear pocket with reflective laser-cut drain holes plus an extra pocket with waterproof zip adds extra practicality and storage space.

Size Guide

CHEST     WAIST     HIPS       INSEAM    
XS    79CM 63CM 87CM 75CM
S 84CM 68CM 92CM 76CM
M 89CM 73CM 97CM 77CM
L 94CM 78CM 102CM 78CM
XL 99CM 83CM 107CM 79CM

Tech Spec

  • Rain or Shine RoS engineering provides insulation and breathability for cold and dry rides, with effective waterproofing for wet rides
  • Gore Windstopper 150 fabric provides wind protection with high breathability and effective rain protection
  • Seam sealing on shoulders, reduced seaming and double stitching keep you mostly dry
  • Alpha construction separates wind/water protection layer from insulating layer
  • Partially covered waterproof YKK Vision zip slide easily and lies flat
  • Raw edge waist lies flat and moves with you
  • Raw edge wrist cuffs lie flat for a perfect interface with gloves
  • Stretch fabrics with advanced patterning make for an excellent cloes-to-body fit that still accommodates a wide range of body types
  • Back ventilation
  • Castelli silicone text gripper at wasit keeps jacket from riding up
  • 3 rear pockets with reflective laser-cut drain holes
  • Extra pocket with waterproof zip
  • Weight 399g (Small) 
  • Castelli comfort range: 0-12c

Castelli's own ratings: 

  • Wind Protection - 5/5
  • Water Protection - 4/5
  • Insulation - 5/5
  • Breathability - 4/5
  • Lightweight - 4/5

Who's Behind It?

Q. What do a 19th century Italian tailor, a designer for the Milan Ballet and the first ever lycra cycling shorts have in common?

A. They are all part of a rich 140 year history that's led to today's most recognised brand in cycling: Castelli.

Throw in a heart attack on a famous Italian climb, family feuds, Olympic gold medals and controversy in the pro peloton and it begins to sound more like a Sicilian soap opera than the backdrop to a cycling brand. But then again Castelli is no ordinary brand.

Today, Castelli's scorpion emblem is arguably the single most recognised in cycling. Iconic is an overused word these days, but the Castelli brand surely qualifies.

We first discovered Castelli on our year long ride through the Americas in 2010, when our founder Liz (pictured) wore Castelli shorts and loved them, so stocking them seemed an obvious choice. But we're almost as captivated by the story behind the name as the kit itself! For the full Castelli story (it's quite a story!), click here.

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