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Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
  • Soft Water Flask 500ml
Soft Water Flask 500ml
£10.95
Colour

Stay hydrated on every adventure with the KitFox Soft Water Flask — designed for runners, hikers, and outdoor enthusiasts who need a lightweight, leak-proof solution on the move.

This high-performance soft flask features a bite valve for smooth, controlled sips and a wide 40 mm opening for effortless refilling at aid stations or water taps. Its flexible TPU body minimises sloshing, while remaining durable and taste-free for a clean, fresh drink every time.

✅ Leak-proof design – No unexpected spills in your hydration vest or pack.
🌊 No-slosh construction – Keeps your water steady, even while running.
😝 No plastic taste – Made from BPA-free, recyclable TPU for pure hydration.

Compatible with most hydration vest brands, this flask is ideal for trail running, marathons, ultrarunning, hiking, or everyday training. If you're unsure about sizing, just drop us an email — we're happy to help.

💡 Top Tip: Store your KitFox flask in the freezer between uses to help prevent bacteria build-up and keep it fresh for your next session.

Frequently asked questions
What is a running soft flask?

A running soft flask is a lightweight, flexible water bottle designed to fit easily into a hydration vest or running belt. As you drink, the soft body collapses to reduce sloshing and make running more comfortable. The KitFox Soft Water Flask is made from BPA-free TPU, so it’s durable, taste-free, and perfect for runners, hikers, and outdoor adventurers.
Is the KitFox Soft Water Flask compatible with my hydration vest?

Yes — the KitFox Soft Water Flask is compatible with most major hydration vest brands, including Salomon. Its flexible shape and 40 mm wide neck make it easy to refill at aid stations and water taps. If you’re unsure about sizing, just drop us a message and we’ll help you find the perfect fit.
How do I clean my running soft flask?

We recommend hand washing your KitFox flask with warm, soapy water after each use. To keep it fresh between runs, store it in the freezer — this helps prevent bacteria build-up and odours. Avoid using boiling water or dishwashers, as these can damage the TPU material.
Can I put electrolytes or sports drinks in the KitFox Soft Flask?

Absolutely. The KitFox Soft Water Flask can safely hold water, electrolyte mixes, and sports drinks. Just rinse it thoroughly after use to prevent residue build-up or flavour transfer.
Does the KitFox Soft Flask leak?

No — the leak-proof design and bite valve ensure your soft flask won’t spill in your running pack or hydration vest. Whether you’re trail running, racing, or hiking, you can stay hydrated without worrying about leaks or drips.
What size soft flask should I choose for running?

The KitFox Soft Water Flask has a 40 mm wide neck and a 250 mm length, making it the ideal size for most running vests and trail packs. Its flexible body means it collapses as you drink, saving space and reducing bounce.
How do I stop my soft flask from tasting like plastic?

Our KitFox Soft Flask is made from BPA-free, food-grade TPU that’s completely taste-free. If you ever notice a hint of flavour, rinse it with a little baking soda and warm water or store it in the freezer overnight — it’ll be fresh and neutral by morning.
Can I freeze water in my soft flask?

Yes — you can partially freeze your KitFox Soft Water Flask for extra-cold hydration on hot runs. Just leave room for the water to expand and don’t fill it all the way before freezing.
Is the KitFox Soft Flask eco-friendly?

Yes — it’s made from recyclable, BPA-free TPU, designed to be durable, long-lasting, and reduce waste compared to disposable bottles. It’s the perfect choice for sustainable runners and outdoor enthusiasts.
What makes the KitFox Soft Flask different from other running bottles?

Unlike rigid running bottles, the KitFox Soft Water Flask collapses as you drink, preventing sloshing and bounce. It’s lightweight, leak-proof, and compatible with most hydration vests — making it the ultimate hydration companion for trail runners, marathoners, and hikers.

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