LOW-PROFILE CARRY - When carrying water and a few essentials are all that's needed, the Katari/Kitsuma provides a lightweight option that rides close to your back for stability on any trail. RESERVOIR INCLUDED - An Osprey Hydraulics® LT 1.5L or 2.5L reservoir keeps you hydrated all day long and stores in an external hydration compartment to protect pack contents from accidental spills. RIDE STABILITY - Our rolled, soft-edged harness contours to the upper shoulders to keep the pack close to your body and provide stability. Osprey Katari 3 Hydration Backpack