A hydration bladder can be stored in a pocket within and has a feed hole on the top of the backpack. This backpack is made of 1000D nylon, along with UTX clips and heavy duty YKK zippers. It comes with a separate pouch which can be attached or attached with the clips. Backpack dimensions pproximately 470mm x 350mm x 150mm. Additional pack is 330mm x 220mm x 100mm. * Toy Soldier armor plate is not included