FEATURES of the Deuter Pulse Four EXP Hip Pack with Bottle Expandable Compartment Front Stretch Stuff-it Pocket Neoprene Sunglass Pouch Side Mesh Hip Belt Pockets Airstripes Race System Airstripes: Foam profiles reduce the surface contact with the wearer’s back about 80%. This results in fantastic back ventilation 3D-AirMesh: Lined shoulder straps Foam Stripes: With 3D-AirMesh lining are contour-shaped have minimal contact surface and ensure maximum air circulation and stability Mesh Wings on The Hip Belt: Help secure the load and offer great ventilation