Complete your backpack setup with the ultimate hydration system. Custom made premium bladders by Source® use anti-bacterial technology, and Glass-Like™ liners that provide great tasting water and super long life. Features include a weave-covered insulated drink tube, a lockable bike-bottle style push-pull drink valve with a dirt shield and wide mouth screw cap opening. Holds 2 liters and weighs 9 ounces while empty. Version 1.