Castelli flanders ls topcastelli caf on the castelli flanders ls base layer this is the winter base layer choice for riders who like to ride hard designed to wick moisture away from the bodyto keep you drier perforated mesh under the arms further aids breathability the flanders ls might actuallybe the only ls base layer you will ever need for yourcycling needs castelli on the flanders we pulled out all the stops to make what we consider the ideal base layer for mild to cool weather cyc