Sinpaid Computer Laptop Book Backpack Medium- Khaki Large size: black, khahi; Medium size: red, purple, khaki, black; Small size: pink,red, black, purple, khaki. Material : Waterproof Nylon,Size:(Hight*Width*Thickness) 43 cm X 29cm X15cm, Fits most 15.6" inch laptop S type straps design and high breathable mesh, could dissipate some heat heat from the back. Unique back strap, you could lean the backpack against the draw-bar box to relieve the pressure of travel. Special hole for your headphones cables,could listen music more convenient when you walk.