Review: SlingFin Portal 2 Backpacking Tent

Ultralight Backpacking Tent
SlingFin Portal 2
$485, 2 lbs. 14 oz.

Everyone wants a super lightweight tent—which makes sense: Give that your tent is one of the heaviest pieces of gear you carry, it offers great potential for weight savings. But not everyone wants the drawbacks of an ultralight tent, which can include tight living quarters and, in particular, so-so stability in strong wind. Enter the SlingFin Portal 2, one of the sturdiest sub-three-pound tents out there, as I discovered on a six-day, 74-mile backpacking trip in the Grand Canyon and stormy nights camping at Idaho’s City of Rocks National Reserve.

In the Grand Canyon in mid-spring, the Portal 2 stood up to winds frequently gusting to 30 mph or more. And while camping at the City of Rocks in May, it also withstood similar winds—and survived a night of crazy wind events: The tent suffered no damage despite being lifted in the air by the wind—due entirely to the sandy soil not holding stakes well—and sent tumbling into sagebrush. But when the wind started blowing at least 50 mph one evening, I had to take the tent down because I was afraid poles would get snapped; I pitched it again later, after the windstorm passed.

Slingfin Portal 2 with a trekking pole inserted for added stability.
Slingfin Portal 2 with a trekking pole inserted for added stability.

Those were unusual conditions that would trash many three-season backpacking tents, but also a reminder that even the strongest ultralight tents have limits—don’t expect performance approaching the stoutest (and much heavier) three-season or mountaineering tents.

SlingFin carried some technologies from mountaineering tents over to the Portal, to improve stability and weather resistance while keeping it under three pounds. It pitches using two DAC Featherlite NFL 8.7mm poles and one NFL 9mm pole. A trekking pole can optionally be used to prop up the rainfly at the peak of each vestibule, bolstering the tent’s wind resistance and strength under snow loads. Pre-installed internal guylines (similar to Slingfin’s 2Lite Trek) can be tensioned from inside to increase lateral stability when the wind’s blowing—and they add virtually no weight to the tent. (See instructions on installing a second set of internal guylines at

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Slingfin Portal 2 with rainfly doors rolled back.
Slingfin Portal 2 with rainfly doors rolled back.

Ten external guy points are matched to toggles to attach the fly to the poles for added structural strength in multi-directional wind. The toggles also allow rolling the fly up halfway over the tent—opening up night sky views while facilitating a quick switch to full rain protection during the night, if necessary, a very nice feature.

In short, the design gives the sub-three-pound Portal 2 the wind resistance you’d find in tents weighing at least a pound more.

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The Portal 2’s livability compares favorably with leading competitors in this weight class (like the Big Agnes HV UL2), with two doors and vestibules, a snug but tolerable 27.5 square feet of floor area, good length (85 inches) and width at the head (51 inches) and foot (42 inches), and a generous peak height (44 inches). The pole architecture boosts headroom without the hubs found on tents from other brands; Slingfin told me they consider hubs a “weakness.” There are seven internal pockets: two each on the ceiling, at the head, and on the sides and one at the foot.

All of the above attributes are noteworthy in a tent that’s under three pounds, although the packed size of 14×5 inches is typical for a tent in this category.

The offset vestibules each have 8.4 square feet of storage area, similar to many lightweight two-person tents.

Ventilation is good, thanks to the mesh interior canopy, vents high on both vestibule doors that can be propped open with struts that still provide full rain protection even when open. Having two doors, of course, greatly improves any tent’s ventilation. Both vestibule doors roll back to create openings nearly the size of the tent’s side walls—which, combined with the ease of rolling back the rainfly, gives the tent a wonderful, open-air feeling on clear nights—and can be kept open in light rain because the drip line doesn’t allow rain inside the tent.

It’s not the fastest three-season tent to pitch; trekking poles aren’t required (and unnecessary in calm weather) but do improve stability, and add time to the job. But it’s easy and faster after you’ve done it once or twice. Matching reflective tabs on the rainfly and tent body make pitching easier.

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The Portal 2 is built with more durability than many ultralight tents. It uses 20-denier nylon ripstop in the floor, 15-denier nylon no-see-um mesh in the tent body, and an 1800mm, 10-denier nylon 66 ripstop silicone rainfly that, unlike PU coatings, doesn’t absorb water, meaning it won’t stretch and sag when wet. Slingfin employs fabrics with good UV and mildew resistance to extend their life, adds extra zipper sliders to double the lifespan of the zippers, and foregoes PU coatings that deteriorate over time. All stress-point seams are reinforced.

A footprint (sold separately, $67, 5 oz.) protects the tent floor and allows pitching the Portal 2 with only the rainfly, slashing the shelter’s total weight to two pounds two ounces. Alternatively, Slingfin also sells separately a Portal Tub Floor ($106, 7.5 oz.) that has sidewalls to keep water from splashing in when pitching it only with the rainfly, a setup that also weighs just two pounds two ounces.

The Slingfin Portal 2 ultralight backpacking tent in the Grand Canyon.
The Slingfin Portal 2 ultralight backpacking tent in the Grand Canyon.

The Verdict

While barely making the (arbitrary) weight limit for an ultralight tent, the Slingfin Portal 2 carves out a unique space in this category by striking a keen balance between solid stability and livability while weighing under three pounds, making it a good choice for any backpacker who wants to reduce pack weight while getting the wind resistance of a heavier tent.

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See my “Review: The 10 Best Backpacking Tents” and all of my reviews of backpacking tents, ultralight backpacking tents, backpacking gear, and ultralight backpacking gear that I like.

See also my “5 Tips For Buying a Backpacking Tent” and “How to Choose the Best Ultralight Tent for You.”

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NOTE: I tested gear for Backpacker Magazine for 20 years. At The Big Outside, I review only what I consider the best outdoor gear and apparel. See categorized menus of all of my gear reviews at The Big Outside.

—Michael Lanza


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Space-to-Weight Ratio
Ease of Use


The Slingfin Portal 2 strikes a keen balance between solid stability and livability while weighing under three pounds, making it a good choice for any backpacker who wants to reduce pack weight while getting the wind resistance of a heavier tent.


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Leave a Comment

14 thoughts on “Review: SlingFin Portal 2 Backpacking Tent”

  1. Unbelievably bizarre. I first saw this photo an realized I know that exact spot! My two friends and I were there weeks before you. It’s the optimum location overlooking the river. At the time I was using a Tarptent. I recently purchased a Slingfin Portal and plan to use it next week on my trip to Panamint City, followed by Evolution Valley in mid-July as well as shorter backpacks in between.

    Great article. Thank you.

    Thomas Greteman

  2. Hi,

    Last summer I loaned my MSR Hubba Hubba 2-person tent out and they put it away wet and left it like that for a month or so in hot weather. I finally had to go get it and discovered that the floor was a gooey mess. The waterproofing had broken down. I have read though that MSR has developed an improved product that will last much longer. My question is this. I notice that the MSR Hubba Hubba NX2 seems very similar in design and features as the Slingfin Portal. Which would you recommend? Thanks, Brian.

    • Hi Brian,

      Sorry to hear about your Hubba Hubba. Sounds like it got mold, understandable in those conditions.

      I think there are some differences between the MSR Hubba Hubba NX 2 and the Slingfin Portal 2. The Hubba Hubba has a bit more floor space but significantly less peak height inside, while weighing in 10 ounces heavier. I really like how you can roll the Portal’s fly up halfway over the tent to open up night sky views. I think the Portal’s design features make it sturdier in wind, too. But the Hubba NX Series also employs MSR’s exclusive Xtreme Shield waterproof coating in the 20-denier rainfly and 30-denier, bathtub-style floor.

      Those are the key differences between the tents.

      I hope that’s helpful. Thanks for the comment and keep in touch.

  3. How does the Portal compare to the Big Agnes Copper Spur HV UL2? If you had to pick between the two as your only backpacking tent for 3-4 day 3 season trips which one would you pick? And why?

    • The key differences, while some are relatively minor, include that the Portal weighs a few ounces more and has slightly less interior square footage, but a much better peak height than the Copper Spur HV UL2, which is an excellent tent. Obviously, one big difference is that the Portal requires trekking poles to pitch.

      • The Portal does not require trekking Poles to Pitch.

        You CAN use your Poles to enhance the Portals ability to withstand high Winds and Snowloading, making it much sturdier.
        But you don’t need Poles to pitch it up or use the Tent.

        It’s freestanding.

        I only used toy trekking Poles to support the Tent stability in heavy winds on Scandinavian Fjells and on 2 occasions in Iceland while hiking the Laugavegur Trail.

        Most Times I use the Portal without trekking Pole support but it’s an amazing Feature to have.

        Once again , the Portal doesn’t require Poles to be pitched.

        • On a side note: have you been using the Portal in Iceland? I’m thinking about taking mine there but was a bit worried about the large mesh area and the winds in Iceland.

          • Satrou,

            Maybe Martin will offer some feedback on that. I have not used the Portal in Iceland, but I have camped in Iceland, where it’s often windy and the terrain is often open. Still, where you camp will obviously matter. I think the Portal will be more sturdy than many standard, three-season backpacking tents when using trekking poles to strengthen the Portal’s structure.

  4. Hello Michael,
    Based in good part on your review I have bought the Slingfin Portal 2. I live in Switzerland and trekked in Iceland last year where my Big Agnes UL2 from 5 years ago sort of collapsed in the wind and rain on the lower front side. So I am looking forward to increased stability with this especially in challenging conditions. What I’d like to ask about for colder weather camping which in Iceland was close to freezing with wind and rain is what to expect and how to cope with this sort of weather with the Portal.

    I noticed that the whole inner is tight mesh and the outer vestibules don’t really come all the way to the ground. Do I need to be concerned about wind and eventually snow (admittedly in a rare occasion ) swirling up and into the tent……If so do you have any mitigating tips? For example do I need a warmer sleeping system in a cold environment?

    • Hi Thomas,

      Thanks for asking a good question. Some of the lightest backpacking tents are not built for the harshest conditions that are occasionally encountered on three-season trips. I think the Slingfin Portal 2 is a good choice for your plans if you want a very sturdy tent that’s still lightweight. (Obviously, there are heavier tents with more stability.)

      My biggest tip would be to use two trekking poles to augment the tent’s poles (as described in my review), adding strength to the structure. I’d also try to pitch any tent in a relatively protected spot if it’s windy.

      I reached out to Tim Hunt at Slingfin, who had a hand in designing the Portal 2, and asked him to comment on your question. Here’s what he wrote back to me:

      “Sounds like pretty ideal conditions for the Portal. It’s for people pushing the boundaries of 3-season camping with some mild occasional winter conditions. The Portal’s mesh will block a fair amount of airflow, though admittedly not as much as a solid nylon inner tent. This airflow is what keeps condensation to a minimum. There’s enough overlap between the walls of the tub floor and the fly that falling snow isn’t much of an issue, especially when the fly is tightened all the way down. You might get a few errant flakes finding their way onto the mesh, but nothing serious, in my experience. Spindrift in high winds presents more of an issue, which usually happens when you’re camping on a snowpack in very cold conditions. When snow is blowing up off the ground it’s more likely to find its way under the flysheet, but at this point you’re really getting into the kind of conditions that warrant a dedicated 4-season tent. If I’m worried about snow or drafts coming in through the vestibule, I try to orient my backpack in the vestibule so that it blocks the gap between the flysheet and the ground on the side that the wind is coming from.”

      I hope that’s helpful. Safe travels. Keep in touch.