Castelli Alpha Ros Light Jacket 2018

It dips well into temperatures where you might normally reach for a full protection jacket, yet the surprising breathability makes it still comfortable in temps when you may have worn arm warmers and a vest in the past.

We call this functional waterproofing because while we don't guarantee that no drop will ever enter the jacket, we promise you that this is our best effort to keep you warm and dry in the widest range of conditions.

RoS stands for Rain or Shine. It's a label Castelli give to their most advanced products that excel in both dry and wet conditions. For dry conditions, you're looking for comfort along with breathability to prevent you from getting wet and chilled from the inside.

But with wet-weather clothing, you're looking for protection that will help you stay warm by keeping the rain out and letting sweat escape. The Alpha RoS Light Jacket ticks both of those boxes. Both the front and back materials represent a significant step forward in rain protection.

These fabrics are used with reduced seaming, and seam sealing where necessary. Features Lightweight double-layer wind jersey with significant rain protection Windstopper (R) 150 front and sleeves Nano Flex Xtra Dry back for the most significant nonmembrane water protection available ProSecco Strada inner liner with 2nd front zip Waterproof YKK (R) Vislon (R) zipper Articulated collar that fits better whether you're standing or riding Front zippered pocket 3 rear pockets with reflective laser-cut drain holes Raw-edge waist lies flat and moves with you Advanced patterning makes for excellent close-to-body fit Weight:380g.