Hydro Flask Trail Series Ultralight Titanium bottle
Photo credit: Adam Ruggiero

Lightest Insulated Water Bottle: Hydro Flask Launches Titanium ‘Ultralight’ Trail Series

Coffee-loving hikers take note: Hydro Flask has the ‘lightest weight vacuum-insulated bottle currently on the market.’

Weight is king among backpackers — and many employ special hacks to keep ounces to a minimum. Ditching tent stakes, cutting pack straps, even shaving the handle off a toothbrush are common tactics among the ultralight crowd.

But sometimes the answer lies in the material and design of a product rather than a workaround. That’s where Hydro Flask’s new Trail Series insulated mugs come in — specifically, the new line’s flagship bottle, the Ultralight Titanium bottle. With a titanium body, titanium cap, and titanium rivets securing the carry strap, it weighs a scant 7.8 ounces.

And while that still leaves it more than an ounce heavier than your standard 32-ounce Nalgene, and quite a bit heavier than a cheap single-use plastic water bottle, the Ultralight Titanium’s vacuum insulation means it can handle cowboy coffee in the morning as well as it does ice-cold water.

In short: I used the Hydro Flask Ultralight Titanium vacuum-insulated bottle over the summer. I took it on hikes, commutes, and on afternoon exercise pursuits. To be sure, it’s the lightest insulated bottle I’ve ever tried. Its minimalist aesthetic complements its svelte profile well.

While its price and some tactile quirks mean it won’t find its way into everyone’s pack, backpackers may appreciate it as an ultralight, between-source water carrier.

First Look: Hydro Flask Ultralight Titanium Trail Series Bottle

Hydro Flask Trail Series Ultralight Titanium bottle

At 21-ounce capacity, this titanium bottle won’t hold a day’s worth of hydration. But as a complement to water-purification products like MSR’s TrailShot or iodine tabs, it can offer an on-trail water source to help hikers get from point A to point B. Those looking to hike longer days with uncertain sources of water will want a larger vessel.

Still, the Ultralight Titanium bottle keeps a narrow profile thanks to its standard-mouth design. So it will slide easily into a pack. Or, even better, its carrying loop means it can be clipped to the outside of a pack — and its sub-half-pound weight will prevent it from being too much of a burden.

In my testing, I did note one noticeable drawback. Because both the vessel cap and body are titanium, the threads between the two have an unpleasant, squeaky metallic rub when engaged. When filling up before leaving camp, this won’t be a significant issue. But if you bring it to the coffee shop on a busy weekend, you might catch a look.

Hydro Flask Titanium Bottle: Durability, Thermal Performance

I also took the liberty of dropping, kicking, and generally mishandling the bottle — all in the name of testing. It received a few minor dings but otherwise withstood any major damage without cracking. As a result, I expect it will prove a long-lasting and durable bottle.

As for thermal performance, Hydro Flask advertises the double-wall Ultralight Titanium bottle will keep hot drinks “piping hot” for up to 6 hours and cold drinks cold for up to 24 hours.

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Final Thoughts

So, is this the bottle of the future? Well, it’s probably a start. Titanium remains a cost-prohibitive premium for those who need to save weight. But it’s finding more and more uses in the outdoors, from camping to hiking and beyond.

The Hydro Flask Trail Series Ultralight Titanium bottle opens the door for insulated “ultralight” vessels. Other titanium bottles exist, but none with double-wall vacuum insulation. While I wasn’t thrilled with the cap’s haptic feedback, it’s a small price to pay for the lightest insulated bottle on the market today. Of course, the actual price — $100 — is a pretty big price to pay.

But for those who need an insulated option and count grams before blessings, this bottle provides the latest tech and design to meet those needs. The Hydro Flask Trail Series Ultralight Titanium is available now.

Adam Ruggiero

Adam Ruggiero is the editor-in-chief of GearJunkie and a fan of virtually all sports and activities. From biking, running, and (not enough) surfing, to ball sports, camping, and cattle farming — if it's outside, it's worth doing. Adam graduated from the University of Minnesota with a BA in journalism. Likes: unique beer, dogs, stories. Like nots: neckties, escalators, manicured lawns.