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    Rendezvu
    On a mission to get more people to enjoy the outdoors© 2026
    RendezvuAboutFor HostsFor BrandsFor Shoppers
    LegalTermsPrivacy
    ResourcesDocsContactFeedback
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    Brand: UltrAspire

    Category: Running Vests & Packs

    Recommended by Keifer Gilbert, Endurance Enthusiast, Adventurer, Coach, Father, Sober Dude — Phoenix, AZ

    The Mountain Racer Waist Pack is a robust and spacious 3-liter pack designed for adventurers who demand durability and comfort in challenging terrains. Its innovative design and high-quality materials ensure that your essentials are securely stored and easily accessible during your outdoor pursuits. 1. Constructed with EnduraMesh XT™, a high-density blend featuring 30% UHMWPE ripstop for exceptional strength and durability. 2. Generous 3-liter capacity allows for ample storage of essentials, making it perfect for long hikes or trail runs. 3. Front kangaroo-style pocket includes an internal sleeve for your phone and a zippered pocket for organized storage of smaller items. 4. Two large side pockets equipped with compression straps and cord locks to securely hold sensitive gear. 5. Rear compartment accommodates an 800 mL Softflask with a locking cap, ensuring hydration is always within reach. 6. Compatible with UltrAspire Light Bracket for easy integration with various Lumen light models, enhancing visibility during low-light conditions. 7. Available in four sizes (Small to Extra Large) for a customizable fit, ensuring comfort during extended wear. The Mountain Racer Waist Pack is ideal for trail running, hiking, and other outdoor activities where lightweight and reliable gear is essential. It excels in rugged environments, providing secure storage for gear while maintaining comfort and accessibility. Perfect for outdoor enthusiasts of all skill levels, this pack is designed for those who venture into the mountains year-round, ensuring they are well-prepared for any adventure.

    Price: $124.95

    Expert Review

    Without a doubt the most underrated waist belt on the market. Second to none in terms of storage capacity, materials used and overall fit. Absolutely no bounce in this thing and it can store both a 1L and 800ml flask. I'm a heavy sweater so this thing has been a game changer for me. It also is compatible with UltraSpire's waistlight system, which simplifies race day logistics in many ways.

    Recommended by Keifer Gilbert

    Frequently asked questions

    What does Keifer Gilbert say about the Mountain Racer Waist Pack?

    Without a doubt the most underrated waist belt on the market. Second to none in terms of storage capacity, materials used and overall fit. Absolutely no bounce in this thing and it can store both a 1L and 800ml flask. I'm a heavy sweater so this thing has been a game changer for me. It also is compatible with UltraSpire's waistlight system, which simplifies race day logistics in many ways.

    Why does Keifer Gilbert recommend UltrAspire?

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    Mountain Racer Waist Pack by UltrAspire — recommended by Keifer Gilbert
    Accessories

    Mountain Racer Waist Pack

    Keifer Gilbert
    Keifer GilbertRecommended in “10 Products I Actually Use”
    Without a doubt the most underrated waist belt on the market. Second to none in terms of storage capacity, materials used and overall fit. Absolutely no bounce in this thing and it can store both a 1L and 800ml flask. I'm a heavy sweater so this thing has been a game changer for me. It also is compatible with UltraSpire's waistlight system, which simplifies race day logistics in many ways.
    Purchasing through this link directly supports Keifer
    Accessories

    Mountain Racer Waist Pack

    Keifer Gilbert
    Keifer GilbertRecommended in “10 Products I Actually Use”
    Without a doubt the most underrated waist belt on the market. Second to none in terms of storage capacity, materials used and overall fit. Absolutely no bounce in this thing and it can store both a 1L and 800ml flask. I'm a heavy sweater so this thing has been a game changer for me. It also is compatible with UltraSpire's waistlight system, which simplifies race day logistics in many ways.
    Purchasing through this link directly supports Keifer
    Mountain Racer Waist Pack by UltrAspire — recommended by Keifer Gilbert

    Keifer Gilbert recommends the UltrAspire Mountain Racer Waist Pack for running vests & packs. Without a doubt the most underrated waist belt on the market. Second to none in terms of storage capacity, materials used and overall fit. Absolutely no bounce in this thing and it can store both a 1L and 800ml flask. I'm a heavy sweater so this thing has been a game changer for me. It also is compatible with UltraSpire's waistlight system, which simplifies race day logistics in many ways.

    Is the Mountain Racer Waist Pack a good running vests & pack?

    Yes — Keifer Gilbert recommends the Mountain Racer Waist Pack by UltrAspire as their running vests & packs pick. Without a doubt the most underrated waist belt on the market. Second to none in terms of storage capacity, materials used and overall fit. Absolutely no bounce in this thing and it can store both a 1L and 800ml flask. I'm a heavy sweater so this thing has been a game changer for me. It also is compatible with UltraSpire's waistlight system, which simplifies race day logistics in many ways.

    More from Keifer Gilbert's 10 Products I Actually Use

    • Norda 001A - M - Abyss
    • UltrAspire Traverse Hydration Pack
    • Death March Running Company DMRC Local Legend 5-Panel Hat
    • Heivy Pink Himalayan Salt 1000 MG - High Quality
    • HYPERLYTE H1
    • Leki ULTRATRAIL FX.ONE SUPERLITE
    • Precision Hydration PF 90 Gel
    • Mount to Coast H1

    View Keifer Gilbert's expert gear recommendations on Rendezvu