The shell of a jacket, vest or pants refers to the material that lines the inside of the garment. Most of our jackets have a removable insulated liner and a mesh shell between the liner and the body of the jacket (essential for venting).
Mesh Shell Detail
Mesh (shown left) is the best choice of shell material in a vented jacket because it allows maximum airflow through the vents and around your torso. In a vented jacket a vest like area around your torso is mesh and the sleeves remain nylon.
Nylon is an good shell material because it is extremely durable and has a silky smooth texture that feels good against your skin.