Deuter Compact 3.0 liter hydration backpack features 3D AirMesh lined shoulder straps system to enhance comfort and airflow. Features, anatomically formed straps for comfortable movement while chest strap further secures the fit. Breathable Mesh wings on the hip belt. Two contour-shaped layers of knobbly foam with AirMesh lining. Minimal back contact provides maximum airflow. Flexible aluminium construction stays within the foam profile, while stays can be bent to fit user's back contour. Due to sanitary reasons, I removed the bladder and it is not included.