Altosy Packs Women's Hiking 40l Backpack 8347 nylon Imported Powerful Aircomfort system, breathable perspiration, relieve burdened Powerful Bear Breathable System, the heat could quickly spread out, avoiding the embarrassment of sweat, also it's more comfortable for your back A small front pocket with open by buckle ,2 front zipper pockets for putting small thing, a main pocket,A big main pocket with a compartment for Hydration Bladder, A bottom rain cover pocket, 2 Hipbelt Pockets cell phone/MP3 player there is a compartment in the main pocket design for putting Hydration bladder Size: 20"x13"x7.8" Capacity: 40L