Light and airy. This is my second Castelli Climber's jersey. Have yet to find anything lighter or cooler. I wait till they are on sale. I just like the look and fit. Standard Castelli fit. I go up one size in their bibs to a large and two sizes for their jerseys (from medium to x-large). I do some weight lifting so that might account for the two size bump for Castelli jerseys. Prefer a tight fit. 5'10 34 176 lbs.
I know Castelli clothing generally run small but fit on this jersey this is next level out of scale. I am 6'4', 190 lb with 41 inch chest, 35 in waist and size XL was not even close ... way to small across the shoulders, chest, and even the sleeve openings despite a size chart that indicates an XL to be dead on my measurements. I have a variety of other Castelli jerseys in XL that fit nicely so it is frustrating to find such wild variation in sizingfit between different models of jerseys.