Review: Hydrapak SF500 and SF350 SoftFlasks

I’ll be honest: most of the stuff we review on Singletracks is a variation or improvement on an existing product: apparel, tires, components…. even whole bikes don’t really change all that much from one year to the next. Once in a while, though, we get a truly new product, and the SoftFlask is just such an item.

As the name implies, Hydrapak has created a water bottle from the same excellent material as their hydration pack bladders.

Within moments of the box arriving, both SoftFlasks had been commandeered by my wife and daughter, and I had to fight to get them back just to do the review! I tested the intuitively-named SF350 and SF500 (milliliters), and from the very first use I was hooked.

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As mentioned, the construction is really just a new take on Hydrapak’s tried-and-true bladder design–however, there are a number of specific changes to make it work as a bottle. The exterior surface is textured to make it non-slip. The top employs a sports bottle-type bite valve, and includes a nifty shut-off. There is a fabric loop for carrying it while walking or running, and finally, an anchor point on the bottom for strapping it to a backpack or other mount point.

Photo Credit: Hydrpak

Hydrapak uses BPA and PVC-free Thermoplastic Polyurethane (TPU) similar to some phone cases. The result is a flexible, grippable container that doesn’t have any off flavors and won’t give you cancer. Win/win!

Using the SoftFlask

On the business end, the SoftFlask works like any other sports bottle; the obvious difference is the squishy body. Since it isn’t a rigid shape, it can easily be stuffed into a pocket or other space that wouldn’t normally fit a bottle of the same volume. The twist-lock closure keeps it from leaking, but is also a little hard to work with one hand. While riding, I tend to leave it unlocked, and I haven’t had any issues.

It is worth noting that these do not work in a bottle cage. I guess it’s fairly obvious that this would be a no-go, but hey, I tried it anyway…

The bite valve works as expected, with a decent  flow rate and no leaks.

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Another neat feature, since it is soft, is that is shrinks as you drink the contents, taking less and less space as you go–and of course you can also squeeze it while drinking to get even more liquid in one gulp.

As an added bonus, for all you winter fat bikers looking for a solution to cold weather hydration, these are just the ticket. They can be comfortably stowed in an inside pocket where your body heat can keep your drink of choice from freezing.

Clean Up

Here’s my favorite part: after using the SoftFlask, just toss it in the dishwasher (top rack) and go. This keeps any funk from building up and of course sanitizes it, and also makes it feasible to to fill it with flavored drinks out on the trail. Lately, I have been putting straight water in my hydration pack and Tailwind Endurance Drink in the SoftFlask. (I can neither confirm nor deny that I have tried them with beer.)

Off the Bike

As I mentioned, my wife and daughter immediately made off with my sample set. They have been used for skiing, hiking, running, and road trips (they fit nicely in seat back pockets). Through it all, they have been tossed, dropped, sat on, stepped on, run over by bike tires, fallen on while skiing, put through the dishwasher numerous times… and they still look and work as good as new.  The final verdict from the family is that I’ve been directed to purchase several more before our vacation this summer.

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To be honest, there’s really nothing to complain about here. To really nitpick, the twist lock can be a little hard to work at first, but it loosens up with use, and gets easier once you get a feel for it. Also, the sides aren’t marked with volume measurements, but again, I’m reeeeeeally nitpicking here.

Bottom Line

At $18.95, $19.95 or $20.95 for the 350ml, 500ml, and 750ml sizes, respectively, these aren’t the cheapest water bottle on the market., but when you factor in just how darn versatile and durable they are, it’s actually a pretty good deal.

Whether you’re looking to pack something other than water without mucking up your main hydration system, trying to bike without a pack, or you just want a neat bottle that can be stowed almost anywhere, the Hydrapak SoftFlask is definitely worth checking out. Just don’t let your kids or spouse find it, or you’ll never see it again…

Thanks to Hydrapak for sending over the SoftFlask for review!

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