The berkeley daypack from jack wolfskin is an incredibly versatile and comfortable bag that has many different pockets of varying sizes that makes it jack wolfskin s most popular daypack the berkeley s carry system has an ergonomic design to distribute load over a larger surface area and minimises pressure points on the shoulders by the use of extra wide shoulder straps padded shoulder yoke and the comfortable and robust ev foam back contact surfaces which makes you feel like you are not even ca