Sierra Designs Revival 50 Backpack 150D Nylon Rain Dobby / 315D Cordura Weekend-plus backpack equipped with comfortable Fulcrum suspension system Die-cut foam shoulder straps with mesh panels; thermo-molded, pre-curved waist belt Top-loading main compartment; Super-Size-Me front pocket; security pocket Load-lifter/stabilizer straps; hydration sleeve and pair of water bottle pockets Integrated bottle opener; available in small/medium and medium/large sizes