If you buy something using links in our stories, we may earn a commission. This helps support our journalism. Learn more. Please also consider subscribing to WIRED

It's reasonable to expect a few teething problems with a company's new product, even more so when it's a category the brand hasn't ventured into before. That's what I expected when I first heard about Sea to Summit's new ultralight tents: the freestanding Telos and the slightly cheaper, semi-freestanding Alto. But the company, which typically makes outdoor stuff sacks, sleeping pads, and camping cookware, came right out of the gate with some of the best tents on the market.  

I tested the Alto TR1, but both of these are high-end, lightweight tents aimed at backpackers willing to pay a premium to trim weight from their loads and those who don't mind being gentler on their gear than car campers.

At 33 ounces, the one-person Alto TR1 is one of the absolute lightest double-wall tents. It's a three-season tent, so it's suitable for spring, summer, and fall conditions. The inner wall is made mostly of mesh, so you can keep the door zipped shut in warm weather to keep out the bugs and still prevent the interior from getting stuffy.

Above the sleeper's head there's a large vent in the outer wall that can be propped open or closed. For balmy nights, it did a good job of ventilating the tent, though bugs loved to crawl and fly in there and roam around between the inner and outer walls of the tent. They couldn't get inside the actual tent, since the inner wall was still sealed up, so it didn't present much of a problem beyond seeing a bunch of gnats hanging over me in the mornings. I'd have liked a mesh panel over the vent opening to prevent this.

The TR1 isn't the only Alto tent. There's also the Alto TR1 Plus, which is what's referred to as a “three-season plus” tent. It adds 4 ounces and does away with much of the mesh on the inner wall to deal with colder temperatures. You can also find larger, two-person versions: the TR2 and TR2 Plus.

Being a semi-freestanding tent, it's possible to mostly set up the TR1 without pulling out the guylines and staking them down. Mostly. It'll hold its general shape, but you'll need to stake out certain corners of the tent to maximize interior space.

I brought the Alto TR1 to Hawaii on hikes along the Kalalau Trail on the island of Kauai and the Muliwai Trail on the island of Hawaii, otherwise known as the Big Island. In both spots, I set up camp right alongside the water on the north coasts and was treated to, at times, ferocious winds and all-night storms. 

I staked all the guylines with MSR Groundhogs, and the Alto performed better than I expected for a semi-freestanding tent. (They typically don't fare as well in intense wind conditions as freestanding tents.) After it held strong during the first big storm, allowing me to have a full night's sleep, I felt confident enough to leave it standing while I went on a four-hour day hike. Its long guylines held up to strong winds better than some freestanding tents I've used. 

That said, if I was going to use a tent in regions where it's impossible to get a stake into the hard-packed ground, such as many southwestern US deserts, I'd consider the freestanding Telos instead, though Sea to Summit doesn't make a one-person version. (It should.)

The DAC poles are lightweight, strong, and couldn't be easier to assemble and disassemble. Above the peak of the tent, a horizontal pole stretches out the walls and creates a nice, wide attic. When I needed to get dressed in the tent, I had no problems kneeling without hitting the top of my head. Tent manufacturers list a maximum height—42.5 inches for the Alto TR1—but what the specs sheets don't tell you is how roomy that attic is. In many other tents, such as the Big Agnes Copper Spur UL1, I had to crunch down like a snail to avoid touching my head to the roof.

The Alto TR1 comes with a rigid, translucent Lightbar that attaches to the inner part of this horizontal pole. Rather than carrying a separate lantern, you put a headlamp (or two) in the Lightbar. Then you can have light without having to wear your headlamp inside your tent. The Lightbar is optional and can be left at home to save weight and space. It's nice, since I dislike wearing my not-always-comfortable headlamp before bed. But I'd still rather just use a 0.65-ounce MoonLit LED Micro Lantern clipped to an interior gear loop and save my headlamp for darker nights on the trail.

There's only one pocket for storing light items: a horizontal, ground-level pocket near the head on the side of the inner wall. You can buy an Alto Gear Loft ($20) that gives you a place to stash light gear above you where your feet can't bump them. It's cheap, but I think tents should come with gear lofts standard.

Good zippers are a yardstick by which to measure the worth of a tent, especially a lightweight one, where the zippers are often smaller and tend to snag on the fabric (potentially tearing it). The Alto's zippers are as smooth as butter soaked in more butter. There are two zippers on the reverse-L-shaped door on the tent's inner wall, like most tents. 

Unlike most tents, you can pull either zipper around the 90-degree bend for the whole length of the zipper track. I enjoyed this more than I'd like to admit. I could zip the whole door open or closed with one zipper (or both bunched together), rather than fiddling with two zippers and then making doubly sure that they're cinched together tight enough that no tiny, weird bugs were going to invade through a small space between them.

Overall, Sea to Summit delivered a fantastic tent. Not only is it stable and roomy, but it's also one of the lightest tents I've ever used—amazing feats considering it's the brand's first tents. I can't wait to see how the Alto and Telos evolve as Sea to Summit improves them over the coming years.