The Midshell (R) product with comfort mapped weather protection and air permeability for extended multi-environment use. The BLACKYAK CASTANA MIDSHELL (R) combines the unique windproof and rain resistant properties of our YAK SKYN (TM) Membrane with the enhanced air permeability and comfort of our YAK XD (TM) P-S extreme durability stretch textile. Black Yak Castana Jacket Mens | Charcoal | Size Large