Camelbak Octane 18X Hydration Pack Air Mesh back panel, Antidote lumbar reservoir . Ultra-light 3D Mesh harness w/ Independent SuspensionTM, gel pocket and SliderTM Sternum Strap Designed to carry extra layers, ultra-light weather protection, food, head lamp, trail map, compass, trekking poles Stash pocket on waist belt for easy access to gel or essentials. Expandable zip compression