Osprey Men's Viper 5 Hydration Pack 100% Nylon Imported Main compartment with sleeves for pumps A removable, 20mm ErgoPull webbing hipbelt keeps the pack stable New direct zip access hydration sleeve for fast loading and Osprey Hydraulics reservoir included Quickly secure a helmet to your Viper Series pack with the LidLock. A wide panel access to the main compartment with sleeves for pumps and tools. A zip access pocket with protective embossed fabric that fits sunglasses, cell phones or other electronics The total capacity of the product is 5L. This pack comes with a 2L Hydration reservoir and contains an additional 3L of storage.