Mazama Dualocity 64 oz. Dual Chamber Hydration Reservoir Replacement - Compatible with Most Larger (3L) Hydration Packs Carry both electrolytes and water so you stay energized and cramp-free Each chamber holds 32 oz (large bottle of sport drink) of fluid, just fill and go Use as a single reservoir or split into two chambers with sealing clip Left and right drink tubes with high-flow bite valves and magnetic retainers Anti-bacterial materials, No BPA or PVC