The original Camelbak product, continuously improved and upgraded, then battle-tested by hundreds of thousands of troops worldwide. Quick release should straps, improved fold-down fill port cover, D-ring attachment points and a fully insulated reservoir compartment are just a few of the innovative features included in this pack. It comes with the Mil Spec Antidote. More than just a reservoir, the Antidote redefines the ultimate delivery system for an Operator's water supply and provides maximum adaptability for changing missions or combat environments. It includes a quick link exit port and ql hydrolock bite valve adapter allowing the tube to click off for faster refilling with auto shut-off. It also features a new fill port with air-light 1/4 turn open/close for quick, secure seal that can't be over-tightened.