Designed for cyclists who want to lighten their load without sacrificing the essentials, the Osprey Seral 4 is a technical and ergonomic lumbar pack. With a volume of 4 liters, it features a new-generation 1.5-liter Hydraulics™ reservoir and an improved magnetic system for quick access to the hydration tube, even when you're in the middle of a ride.

This lower-slung hip pack design offers excellent weight balance and freedom of movement, ideal for short to medium bike rides.

An ultra-stable lumbar pack, even on rough terrain

The lumbar support has been perfectly optimized for cyclists:

1. AirScape™ back panel with ribbed foam and central ventilation channel
2. Wraparound mesh waistbelt with practical zippered pockets
3. ErgoPull tightening system for quick and precise adjustment
4. Side compression straps that reduce bounce and ensure a perfect fit
5. The bag stays in place even during technical descents, while ensuring excellent ventilation.

Keep everything you need close at hand with the Seral 4 lumbar bag

Don't be fooled by its small size: the Seral 4 is designed to carry all your repair and refueling essentials.

• Large zipped main compartment
• Secure inner pocket
• Hydraulics™ 1.5 L lumbar reservoir included
• Magnetic attachment point for hydration valve
• Attachment for flashing light + reflective elements
• Waistband pockets for snacks, tools or multi-tools

A technical and eco-friendly waist bag

Like the entire Osprey range, the Seral 4 is made from recycled materials and using environmentally friendly processes:

• Main fabrics and base 100% recycled, bluesign® and GRS certified
• PFAS-free water-repellent treatments
• BPA, phthalate and PVC-free reservoir