Brand: HydraPak
Category: Running Water Bottles & Flasks
Recommended by Clare Farrow, ultrarunner — Colorado
The UltraFlask™ Speed 500ml 2-Pack is designed for athletes seeking a lightweight, flexible hydration solution that fits seamlessly into their gear. With its innovative SpeedFill™ Cap and durable construction, this flask ensures quick refills and reliable performance during any activity. 1. Wide form design allows for easy handling and stability during use. 2. Constructed from lightweight TPU material, ensuring durability without added weight. 3. 3D welded bottom provides enhanced stability and prevents leaks. 4. SpeedFill™ Cap enables rapid refills, perfect for on-the-go hydration. 5. Soft and pliable structure allows for compact packing in most running vests and backpacks. 6. Each flask holds 500ml (17oz), ideal for extended outdoor activities. 7. Designed specifically for trail running, hiking, and other dynamic sports. The UltraFlask™ Speed 500ml 2-Pack is perfect for runners, hikers, and outdoor enthusiasts who require a reliable hydration solution. It excels in various environments, from rugged trails to urban runs, making it suitable for both casual joggers and seasoned athletes. Ideal for warm weather activities, this flask ensures you stay hydrated without the bulk, allowing for a streamlined experience during your adventures.
Price: $31.2 - $39
- Who it's for
- Trail runners and ultramarathon racers who carry water in vest pockets, especially those doing long efforts like 100-milers. Also suits backcountry users who pair soft flasks with a filter cap for lightweight water management.
- What people are saying
- Hosts consistently praise the minimal slosh, easy refilling, and vest-pocket fit; the snap/Speedfill cap gets specific credit for on-the-go drinking. One host recommends sizing up to the 600ml for longer mountain runs, suggesting 500ml can feel limiting.
- Worth noting
- The Speedfill cap can come undone when stored inside a pack without the filter top — worth monitoring. Works with filter caps for backcountry use.
Clare Farrow's review
the best soft flasks in the game. aid station volunteers are blown away when i roll up with these bad boys
Recommended by Clare Farrow, ultrarunner
Frequently asked questions
Who is the UltraFlask™ Speed 500ml 2-Pack for?
Trail runners and ultramarathon racers who carry water in vest pockets, especially those doing long efforts like 100-milers. Also suits backcountry users who pair soft flasks with a filter cap for lightweight water management.
What do experts say about the UltraFlask™ Speed 500ml 2-Pack?
Hosts consistently praise the minimal slosh, easy refilling, and vest-pocket fit; the snap/Speedfill cap gets specific credit for on-the-go drinking. One host recommends sizing up to the 600ml for longer mountain runs, suggesting 500ml can feel limiting.
What should you know before buying the UltraFlask™ Speed 500ml 2-Pack?
The Speedfill cap can come undone when stored inside a pack without the filter top — worth monitoring. Works with filter caps for backcountry use.
What does Clare Farrow say about the UltraFlask™ Speed 500ml 2-Pack?
the best soft flasks in the game. aid station volunteers are blown away when i roll up with these bad boys
Why does Clare Farrow recommend HydraPak?
Clare Farrow recommends the HydraPak UltraFlask™ Speed 500ml 2-Pack for running water bottles & flasks. the best soft flasks in the game. aid station volunteers are blown away when i roll up with these bad boys
Is the UltraFlask™ Speed 500ml 2-Pack a good running water bottles & flask?
Yes — Clare Farrow recommends the UltraFlask™ Speed 500ml 2-Pack by HydraPak as their running water bottles & flasks pick. the best soft flasks in the game. aid station volunteers are blown away when i roll up with these bad boys
More from Clare Farrow's Pinhoti 100!
View Clare Farrow's expert gear recommendations on Rendezvu
What other hosts are saying
8 experts recommend the HydraPak UltraFlask™ Speed 500ml 2-Pack.
So many flasks, so much water!
Recommended in Cocodona 250
I usually put my filter top on this 500 ml soft flask. With good planning and a filter, I am usually fine with 1 L total water capacity on most of my trips (two 500ml soft flasks). One thing to be mindful of if you are not using the filter cap and are storing this in your pack is that the Speedfill cap can come undone!
Recommended in Fastpacking
Ben Corwin, Hutkeeper and mountain adventurer
Easy to fill and designed to fit a wide variety of pockets, we use these flasks for water and electrolyte drinks alike on long runs. Generally carry two, both up front, but sometimes one is enough if it's not too hot as there is quite a bit of available water on the Leadville 100 course.
Recommended in Teton Crest in a Day
I rec getting the 600ml for longer runs in the mountains
Recommended in Twisted Fork 68km
Best soft water bottles for carrying on the trails
Recommended in 10 Products I Actually Use
I use these bottles for every run, race, and adventure! They limit the "slosh" feeling and don't bounce around. The snap bottle really helps with easy re-fueling.
Recommended in 10 Products I Actually Use
Paired with the long straw
Recommended in Race day Essentials
