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    Rendezvu
    On a mission to get more people to enjoy the outdoors© 2026
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    Brand: Black Diamond

    Category: Running Water Bottles & Flasks

    Recommended by Robyn Lesh, Pro Trail Running Athlete — South Western Colorado

    The Soft Flask W-MX 500 mL by Black Diamond is a lightweight and flexible hydration solution designed for outdoor enthusiasts. Its innovative design ensures easy access to water while minimizing bulk, making it perfect for trail running, hiking, and other active pursuits. 1. Lightweight construction at just 50 grams, making it easy to carry without adding extra weight. 2. 500 mL capacity, providing ample hydration for extended activities. 3. Soft and collapsible design allows for easy storage and reduces sloshing during movement. 4. BPA-free material ensures safe drinking without harmful chemicals. 5. Wide mouth opening for easy filling and cleaning, compatible with most hydration packs. 6. Integrated bite valve for quick and convenient sipping on the go. 7. Durable and puncture-resistant, designed to withstand rugged outdoor conditions. The Soft Flask W-MX 500 mL is ideal for trail runners, hikers, and outdoor adventurers seeking a reliable hydration solution. It performs best in dynamic environments such as trails, mountains, and long-distance events where lightweight gear is essential. Targeted towards active individuals of all skill levels, this flask excels in scenarios requiring quick hydration access, especially during warm weather or high-intensity activities. Its compact design also makes it suitable for seasonal use, ensuring hydration remains effortless year-round.

    Price: $18.71 - $24.95

    Expert Review

    Wide mouthed. Simple flasks. Easy to use lids.

    Recommended by Robyn Lesh

    Frequently asked questions

    What does Robyn Lesh say about the Soft Flask W-MX 500 mL?

    Wide mouthed. Simple flasks. Easy to use lids.

    Why does Robyn Lesh recommend Black Diamond?

    Robyn Lesh recommends the Black Diamond Soft Flask W-MX 500 mL for running water bottles & flasks. Wide mouthed. Simple flasks. Easy to use lids.

    Is the Soft Flask W-MX 500 mL a good running water bottles & flask?

    Yes — Robyn Lesh recommends the Soft Flask W-MX 500 mL by Black Diamond as their running water bottles & flasks pick. Wide mouthed. Simple flasks. Easy to use lids.

    More from Robyn Lesh's CCC by UTMB

    • Sidas Trail running socks - Trail Ultra
    • Sidas Anti-friction cream
    • COROS Heart Rate Monitor
    Rendezvu
    Soft Flask W-MX 500 mL by Black Diamond — recommended by Robyn Lesh
    Nutrition & Hydration

    Soft Flask W-MX 500 mL

    Robyn Lesh
    Robyn LeshRecommended in “CCC by UTMB”
    Wide mouthed. Simple flasks. Easy to use lids.
    Purchasing through this link directly supports Robyn
    Nutrition & Hydration

    Soft Flask W-MX 500 mL

    Robyn Lesh
    Robyn LeshRecommended in “CCC by UTMB”
    Wide mouthed. Simple flasks. Easy to use lids.
    Purchasing through this link directly supports Robyn
    Soft Flask W-MX 500 mL by Black Diamond — recommended by Robyn Lesh
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