CamelBak 2016 Arete 18 Hydration Pack With its lightweight materials and reversible, double-duty design, the Arete 18 is perfect for summit hikes, backpacking trips and travel Antidote Reservoir features easy open/close cap, lightweight fillport and low-profile design Key Pack Features: Converts to reservoir sleeve, secure stash pocket with key clip, removable sternum strap, highly compressible Designed to carry extra layers, food, headlamp, trail map CamelBak Got Your Bak Guarantee: If we build it, we'll Bak it with our lifetime guarantee