Nathan Running Hydration Belt, Black, with 25 oz Hydrapak Soft Flask and ExoSpine Holder

The Nathan Hydration Belt pairs a 25 oz Hydrapak soft flask with an angled ExoSpine holder and a breathable, no-bounce waist pack for hands-free running hydration.

Whether you’re training for a long race or squeezing in daily runs, this lightweight running belt combines a collapsible 25 oz (535 ml) soft flask with structured support and storage so you can carry water, your phone, and essentials without distraction. Built around Nathan’s ExoSpine and Pinnacle FeatherLite construction, the belt compresses where possible and expands where needed, keeping weight low and access fast.

How does this belt keep the bottle secure while I run?

The ExoSpine and angled holder cradle the soft flask to reduce movement and keep the bottle oriented for quick grabs. An adjustable bungee strap gives extra retention so the flask won’t bounce out during faster paces. The belt’s extended side panels wrap the hips to stabilize load and prevent shifting.

• ExoSpine frame that holds the angled flask steady.
• Bungee cord over the bottle for added security.
• Extended side panels to minimize bounce across varied paces.

Will I have room for a phone and small essentials?

Yes — an expandable zippered stretch pocket accommodates most modern smartphones and a few small items like keys, gels, or a credit card. The pocket stretches to fit bulk while zipping closed to keep items secure. Interior mesh improves ventilation so stored items don’t sit against sweaty fabric.

• Expandable zippered stretch pocket fits most phones.
• Streamlined secondary pocket for gels or small valuables.
• Interior air mesh for breathability around stored items.

How comfortable is the fit for long runs or marathons?

Constructed from ultralight materials and breathable mesh, the belt aims to stay unobtrusive over extended wear. An adjustable strap and buckle let you fine-tune tension for a snug, one-size-fits-most fit. The whole system weighs only about 4.9 oz (140 g), so it adds minimal bulk while distributing weight evenly around the waist.

• Ultra-light Pinnacle FeatherLite fabrics reduce perceived load.
• Adjustable belt and buckle for personalized tensioning.
• Breathable interior air mesh to reduce chafing and heat build-up.

How do I refill and carry the Hydrapak soft flask?

The soft flask is designed for easy filling and compact packing when empty — it collapses to save space. The angled pocket gives quick access so you can refill, swap, or sip while on the move. Materials are durable for repeated use and cleaning between runs.

• 25 oz (535 ml) Hydrapak soft flask for generous hydration capacity.
• Collapsible design stores flat when empty to reduce bulk.
• Angled holder enables one-handed access for on-the-go refills or drinks.

Who is this for: Runners who want a minimalist, performance-oriented hydration setup will appreciate this Nathan belt — especially those training for longer distances, runners who prefer a single waist solution instead of a vest, and anyone wanting quick access to a phone and hydration without extra bounce. It suits both men and women thanks to a wide adjustment range and a low-profile design that keeps hydration and essentials close at hand.