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Discover the new standard in ultra-distance running with the AMBITION 4.5L. Designed for minimalist, refined, and optimised performance, this trail running vest sets a new benchmark in freedom of movement and accessibility. Crafted with precision for both trail enthusiasts and elite ultra runners, AMBITION supports any race or training run from 10km to 70km, ensuring you remain agile and unencumbered.

Product Features

  • Lightweight and Minimalist Design
  • Custom Fit
  • Optimised Storage
  • Superior Ventilation
  • Versatile Pole Carrying Options
  • Immediate Access
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Select Type: AMBITION 4.5L
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Product Description

The AMBITION 4.5L is a marvel of compactness and versatility. Weighing a mere 190 grams, this vest provides 4.5 litres of intelligently designed storage, offering extreme functionality and a fit so natural that you'll hardly notice you're wearing it. The high-sitting design allows for immediate and easy access to hydration, nutrition, poles, and adjustments, making it the lightest and coolest way to go further on your runs.

Every element of the AMBITION vest is engineered for performance. The adjustable front sternum straps and unique elastic side lacing system provide a custom fit that caters to almost any body type. This ensures stability, unrestricted movement, and unconstrained breathing, even during the most strenuous activities. The optimal positioning of pockets and adjustments allows for natural, effortless, and intuitive access to your gear.

The lightweight and breathable honeycomb mesh construction ensures excellent ventilation and sweat dissipation without sacrificing durability. AMBITION is designed to carry everything you need on the trail, from hydration and fuel to rain gear and safety kits. It includes multiple pockets both at the front and back, strategically placed for maximum convenience.

The frontal solutions of the AMBITION 4.5L include pockets for two 650ml hydration bottles, two 500ml feed storage pockets, and a 100ml shoulder pocket for safety essentials and quick-access items. The dorsal solutions feature a top horizontal pocket for rain gear, a bottom horizontal pocket for safety kits and headlamps, and a vertical pocket for rain pants and other larger items. Additionally, the vest offers five different pole-carrying options, ensuring flexibility and easy access.

With the AMBITION 4.5L, you can focus entirely on your run. Whether you're navigating a rugged trail or racing towards the finish line, this vest supports you every step of the way. Embrace the freedom of movement and exceptional accessibility that only AMBITION can provide.

Key Benefits of AMBITION 4.5L

  • Lightweight and Minimalist Design: Weighs only 190g, providing a barely-there feel.
  • Custom Fit: Adjustable sternum straps and elastic side lacing system for a secure, personalised fit.
  • Optimised Storage: 4.5L capacity with intelligently positioned pockets for easy access to essentials.
  • Superior Ventilation: Lightweight honeycomb mesh ensures breathability and sweat dissipation.
  • Versatile Pole Carrying Options: Five different configurations for carrying poles.
  • Immediate Access: High-sitting design for quick reach to hydration, nutrition, and gear.
  • Durability: Strong, reliable materials that stand up to the demands of ultra-distance running.

Delivery / Returns FREE UK Delivery orders over £30,00, Next Day Service + FREE UK Returns

Shipping Information - Details

UK Standard Delivery - This means that your goods will be processed as normal and shipped by Royal Mail 48. Ordered goods will usually arrive within 3 - 5 working days for most of the UK mainland. Baskets with a total value (before vouchers and promotional codes are applied) of £30.00 and over will qualify for FREE UK delivery.

UK FREE Delivery - to all of the UK on almost every product, as long as your total basket value is greater than £30.00 (delivery charges are applied to baskets with a total value of less than £30.00). - All FREE Delivery order will be sent via (UK) STANDARD SHIPPING (Royal Mail 48)

Need it Quicker? - Select DPD Next Working Day or Fast Delivery at checkout - Orders will be processed as normal and shipped by either DPD for Next Working Day service (excluding weekends) or the Royal Mail Tracked 24 service, ordered goods will usually arrive within (1 - 2 working days)


Return this item for free - If you change your mind on your purchase, you have a 30 days to return it for a refund or replacement subject to terms. All goods must be in new and unused condition and in their original packaging with all labels still attached

About Instinct

Born on the trails of the French Alps and race approved around the world.

Redefining a hydration pack comes from asking the right questions... introducing analytical observations & first hand experience in running the toughest conditions. At the heart of each revolutionary Instinct product is the desire to achieve a greater degree of function, accessibility and ergonomics; Total liberty of movement, zero obstruction and a second skin fit.