The Oakley Flax Backpack XL is built for a life that’s mobile and ready for anything. Featuring stow and go technology for your lab top, two expansion pockets, and a zip pocket on the outside, plus a holster on the shoulder strap to hang your shades.The main compartment has two mesh pockets, a wide pocket for books, and a special pocket for your MP3 player with a pass-through for your headphone cable. As if that was not enough storage space, the smaller pocket opens into four more mesh pockets.