Rendezvu
    On a mission to get more people to enjoy the outdoors© 2026
    RendezvuAboutFor HostsFor BrandsFor Shoppers
    LegalTermsPrivacy
    ResourcesDocsContactFAQsFeedback
    CommunityInstagramLinkedInNewsletterCareers
    Rendezvu
    On a mission to get more people to enjoy the outdoors© 2026
    RendezvuAboutFor HostsFor BrandsFor Shoppers
    LegalTermsPrivacy
    ResourcesDocsContactFAQsFeedback
    CommunityInstagramLinkedInNewsletterCareers

    Brand: Nathan

    Category: Running Water Bottles & Flasks

    Recommended by Shelby Farrell, Athlete. Marketing Professional. Cat Mom. — Morrisville, Vermont

    Highlights: warm, cold retention, insulated

    Stay refreshed and energized during your outdoor adventures with the Nathan Insulated Soft Flask. This innovative hydration solution combines portability with superior insulation, ensuring your drinks remain cool and refreshing, mile after mile. 1. 18 fl. oz. capacity, perfect for hydration on the go. 2. Insulated design keeps beverages cool for extended periods, ideal for warm weather activities. 3. Soft, squeezable material allows for easy one-handed operation while running or hiking. 4. Lightweight construction ensures minimal bulk, making it easy to carry in pockets or packs. 5. Leak-proof cap prevents spills and ensures a secure seal during transport. 6. BPA-free materials provide peace of mind regarding safety and health. 7. Compatible with most hydration packs and belts for versatile use. The Nathan Insulated Soft Flask is designed for active individuals who need reliable hydration during running, hiking, or cycling. It excels in warm weather conditions, keeping your drinks cool while you push your limits. Ideal for athletes, outdoor enthusiasts, and anyone seeking convenience and performance in their hydration gear, this flask is perfect for races, long-distance training, or casual outings.

    Price: $42

    Expert Review

    The insulation is clutch on super cold and super hot days. It's such a treat to have cold water in your flask when you're in the middle of the desert.

    Recommended by Shelby Farrell

    Frequently asked questions

    What does Shelby Farrell say about the Nathan Insulated Soft Flask - 18 fl. oz. Clear 18 Fl Oz?

    The insulation is clutch on super cold and super hot days. It's such a treat to have cold water in your flask when you're in the middle of the desert.

    Why does Shelby Farrell recommend Nathan?

    Shelby Farrell recommends the Nathan Nathan Insulated Soft Flask - 18 fl. oz. Clear 18 Fl Oz for running water bottles & flasks. The insulation is clutch on super cold and super hot days. It's such a treat to have cold water in your flask when you're in the middle of the desert.

    Is the Nathan Insulated Soft Flask - 18 fl. oz. Clear 18 Fl Oz a good running water bottles & flask?

    Yes — Shelby Farrell recommends the Nathan Insulated Soft Flask - 18 fl. oz. Clear 18 Fl Oz by Nathan as their running water bottles & flasks pick. The insulation is clutch on super cold and super hot days. It's such a treat to have cold water in your flask when you're in the middle of the desert.

    More from Shelby Farrell's Fuel & Flasks

    Rendezvu
    Nathan Insulated Soft Flask - 18 fl. oz. Clear 18 Fl Oz by Nathan — recommended by Shelby Farrell
    Nutrition & Hydration

    Nathan Insulated Soft Flask - 18 fl. oz. Clear 18 Fl Oz

    Shelby Farrell
    Shelby FarrellRecommended in “Fuel & Flasks”
    The insulation is clutch on super cold and super hot days. It's such a treat to have cold water in your flask when you're in the middle of the desert.
    Purchasing through this link directly supports Shelby
    Nutrition & Hydration

    Nathan Insulated Soft Flask - 18 fl. oz. Clear 18 Fl Oz

    Shelby Farrell
    Shelby FarrellRecommended in “Fuel & Flasks”
    The insulation is clutch on super cold and super hot days. It's such a treat to have cold water in your flask when you're in the middle of the desert.
    Purchasing through this link directly supports Shelby
    Nathan Insulated Soft Flask - 18 fl. oz. Clear 18 Fl Oz by Nathan — recommended by Shelby Farrell
    • HydraPak SkyFlask™ Speed 500ml
    • REI Skratch Labs Sport Energy Chews
    • HYPERLYTE H1C
    • Näak Energy Puree | Apple & Maple Syrup
    • Tailwind Nutrition High Carb Fuel

    View Shelby Farrell's expert gear recommendations on Rendezvu