The Alpha RoS Jacket takes the guesswork out of what to wear for any given type of weather. With the RoS (Rain or Shine) design the goal was to make the best-in-class garment for dry, cold weather but offer protection should it rain, without the need to revert to another waterproof jacket layer. This was achieved through new fabrics that offer increased breathability but with improved waterproofness too, as well as clever design details that keep the water out yet provide ample breathability and ventilation. Read more… The Rain or Shine system utilises Gore® Windstopper® 150 fabric for wind protection and the high breathability and effective protection required to ride in the rain. Castelli also incorporates their Alpha construction that separates the wind/water protection layer from the insulating layer leading to better control of ventilation and better moisture evaporation thanks to this separation. The result is a jacket unlike any other that allows you to ride from low-temperature conditions right through to wet and mild conditions. Stretch fabrics with advanced patterning make for an excellent close-to-body fit that still accommodates a wide range of body types. A raw-edge waist that lies flat and moves with you plus the Castelli silicone text gripper at your waist keeps the jacket from riding up. 3 rear pockets with reflective laser-cut drain holes plus an extra pocket with waterproof zip make for a very practical jacket with plenty of storage space. For those of you seeking the ultimate in versatile all-weather, multi-season protection you really need not look any further. Think of this as taking all your winter kit options and distilling it into one incredible do-it-all garment. We think you'll find it's worth every penny.