Upgrade or replace your 50 oz. (1.5 L) reservoir with the CamelBak Antidote Reservoir, the ultimate cure for dehydration. The CamelBak Antidote Reservoir features a quick-snap cap that tightens in just a quarter turn, Quicklink tube attachment, a low-profile fit for unmatched stability and an Air-light fill-port that cuts weight. The fill-port is large enough to fit your hand in for easy cleaning. On either side of the fill-port there are two flip-out dry arms that help keep the bag open for better and faster drying.