Endurance-Ready Stability and Hydration for Technical Trails

The Osprey Duro 6 W-Flasks is a masterclass in hydration vest engineering, purpose-built for runners who require self-sufficiency on long-distance training sessions and ultramarathons. With a 6-liter gear capacity, this vest provides the perfect middle ground between a minimal race rig and a full daypack, offering enough room for extra layers, nutrition, and safety gear without compromising your stride. The pack comes equipped with two 500ml Hydraulics™ soft flasks, which sit securely in the harness pockets to ensure hydration is always within reach and completely bounce-free.

Stability is the Duro 6's standout feature. Constructed from 360° structured stretch mesh, the vest wraps around the body like a garment, distributing weight evenly across the shoulders and chest. The dual adjustable/removable sternum straps allow for a precise, fine-tuned fit that accommodates heavy breathing during steep climbs. Organization is maximized with multiple stretch mesh pockets on the harness for gels and electronics, a zippered main compartment for bulkier gear, and an integrated Stow-on-the-Go™ trekking pole attachment. Sustainable and durable, it is made with 100% recycled nylon and a PFAS-free DWR finish.

Key Features:

• Dual 500ml Soft Flasks Included: Two Hydraulics™ soft flasks with extension hoses sit in the harness for instant access to fluids.
• Bounce-Free Harness: 360° structured stretch mesh and dual sternum straps provide a secure, vest-like fit that moves with you.
• 6L Gear Capacity: Ample storage for mandatory race gear, including a zippered main compartment and front stretch pockets.
• Stow-on-the-Go™ Attachment: Allows you to secure trekking poles to the side of the pack without stopping or removing the vest.
• Harness Organization: Features six open stretch mesh pockets and one zippered harness pocket with an integrated safety whistle.
• Breathable Airmesh Contact: Soft, breathable mesh surfaces prevent hotspots and skin irritation during long efforts in the heat.
• Internal Hydration Sleeve: Compatible with a 1.5L Hydraulics™ LT reservoir (sold separately) for additional water capacity.
• Sustainably Built: Crafted from Bluesign-approved 100% recycled nylon with a PFAS-free DWR finish for eco-friendly performance.