The 1.5 horizontal bladder is standard but you can also add an additional 2L vertical bladder and route it down the other shoulder for maximum hydration during a long race day! The heat reflective back panel will keep it cool so you can stay fresh in the hot sun. Our signature chest harness and shoulder adjuster system provide a solid non-bump fit without a waist belt! If you want to stay light and nimble during a race, this is your go to backpack! • 1.5L Hydration and 2L Cargo • Unique lightweight adjustable chest harness for a rock solid fit • Light, durable outer shell • Optimal AirLine back ventilation • Magnetic tube catcher can be positioned on left or right harness • Auto shut-off bladder bite valve • Heat reflective inner back panel to keep liquid cool or hot • Optional 2L bladder can be added into main storage compartment • Reflective slotted patch allows optional safety light suspension • Optimized fit with or without a Leatt® neck brace • Sizing: One size - XS-XXL