Minimalist Hydration with Maximum Stability

The Osprey Seral 4 is the ideal hydration solution for mountain bikers and hikers who prefer the freedom of a lumbar carry over a traditional backpack. Designed for speed and stability, the Seral 4 features an AirScape™ backpanel with extra-thick ridged foam and a center air channel to provide excellent ventilation while keeping the load close to your center of gravity. This ensures a bounce-free ride, even on technical descents or steep climbs.

This pack comes equipped with a 1.5L lumbar-specific reservoir, which is shaped to sit low in the pack for optimized weight distribution. The magnetic bite valve attaches securely to the waist belt for quick, one-handed hydration without needing to stop. Despite its compact 4-liter capacity, the Seral 4 offers smart organization, featuring a zippered main compartment for essentials like a spare tube and CO2, and dual zippered hipbelt pockets for easy access to snacks and small tools while on the move.

Key Features:

• 1.5L Lumbar Reservoir Included: Custom-shaped reservoir keeps the water weight low and stable for a better center of gravity.
• AirScape™ Backpanel: Ridged foam and mesh provide a breathable, body-hugging fit that prevents the pack from shifting during aggressive movement.
• Magnetic Bite Valve: A powerful magnet keeps the hydration hose securely attached to the hipbelt until you need a drink.
• Bike-Specific Organization: Dedicated internal compartments are sized perfectly for bike tools, pumps, and spare parts.
• Compression Straps: Dual compression straps pull the pack into the small of your back to maintain stability when the reservoir is nearly empty.
• Zippered Hipbelt Pockets: Provide convenient, on-the-go storage for energy gels, keys, or a small multi-tool.
• Blinker Light Attachment: Features a dedicated loop for a rear safety light, enhancing visibility during road transitions or low-light rides.