THE NAME CAN BE MISLEADING.
This jersey started life as a lightweight jersey to make climbing easier. But it turned out to be ideal for all summer conditions. The lightweight fabrics make it extremely comfortable while keeping you dry, but without some of the downsides you might expect in a jersey this light. Castelli used a fabric on the back that blocks 95% of damaging UV rays and stitched in a second layer on the front so that the light fabrics aren't transparent. The 3/4-length zip allows you to open the jersey on climbs while the liner keeps it modest, and the three rear pockets have plenty of space for a light jacket and food. This all-around jersey is brilliant for climbing as well as everything else.