We use a vertical HydraPak high-flow bladder with an auto shut-off bite valve, feed tube routing can be either over the shoulder or under the arm. If you’re looking for impact protection for your back, there is an option to purchase a CE impact tested and certified insert, a handy Hi-Viz rain cover is included should the heavens open to keep the bag dry. And one size fits all! For something with more protection check out the 4.5 Chest Protector GPX Hydra. 1.5L Hydration and 20L Cargo Unique lightweight adjustable harness for a rock solid fit Ready to fit optional CE tested and certified as impact protection: Light, durable outer shell Hi-Viz removable rain cover Fleeced goggle pocket ”Emergency whistle” Dual hydration tube for two-way routing – over the shoulder or the under arm Optimal AirLine back ventilation Auto shut-off bladder bite valve Magnetic tube catcher can be positioned on left or right harness Reflective slotted patch allows optional safety light suspension Optimized fit with or without a Leatt® neck brace Sizing: One size - XS-XXL