The Aspen 38 is a rare ultralight pack designed by and built for women.
Symbiosis Aspen 38 Pack (Photo: Nathan Pipenberg)
Published July 2, 2026 01:35 pm
While she was hiking the Pacific Crest Trail, Sarah Berkley observed three different packs and had a realization: Ultralight packs are made for men. A few years later, when she decided designing her own backpack would be easier than finding the perfect fit off the shelf, she surveyed hundreds of women to find out what they wanted in a pack. The most common request was simple: shoulder straps that didn’t crush their chest. Today, Berkley runs the rare women-owned ultralight brand Symbiosis Gear. Its main product, aspenIs a frameless pack designed to fit women and feminine bodies.

The days of male-dominated hiking and backpacking are long gone. According to the Outdoor Industry Association, there is a roughly 50/50 split between men and women who hike all day, and thru-hiker survey show that about 30 to 40 percent of long-distance backpackers are women. Overall, the outdoor industry has become more judicious in response. Gear size options have expanded rapidly, and the “pink it and shrink it” trend, which disguises ill-fitting men’s gear as women’s-specific, is giving way to intentional design.
But if there’s one area of the backpacking world that hasn’t caught on, it’s the ultralight community. The stereotypical ultralighter is young, male, and white. Most ultralight brands are founded by men. Size and fit options for gear still reflect this, although there are some exceptions. Includes brands with female founders or co-founders toxgarment manufacturer alpine fitAnd wild brush, A woman who runs a cottage backpacker Profiled in 2024.
There is still a long way to go. For Berkley, there’s no clearer example of this phenomenon than the ultralight backpack. “I think a lot of women feel left out,” she says. “Ultralight packs are designed by men and made for men.” The result is a self-satisfaction cycle. Women say ultralight gear is not designed with them in mind and they look elsewhere for gear. Brands that have few female-identifying customers do not design their products with them in mind. With the Aspen, a frameless pack designed specifically for women, Berkley hopes to break that cycle.

In designing the pack, Berkley’s first priority was to dial-in the shoulder strap system. The S-shaped strap helps accommodate narrow shoulders while also providing extra room around the chest. S-shaped straps aren’t new, but Berkley says the curves of the Aspen’s shoulder straps are more pronounced, and therefore a better fit for women with larger busts. An elastic sternum strap with three adjustment points (two separate daisy chains running the entire length of each strap) ensures that the straps fit the shape and size of the body as closely as possible.
Even after finding the fit, Berkley soon realized that building a brand focused on ultralight gear for women came with a big challenge: finding an audience.
“I had this dream of becoming Palante Pax for girls,” she says, giving context. cottage pack manufacturer Which found success by taking advantage of word-of-mouth among thru-hikers and ultralight Reddit posters. “What I learned is that a lot of women are not ultralight, and not only that, they are turned off by labels. When I talked about creating an ultralight pack, I encountered some resistance that I didn’t know was there.”

Even though she considers herself very lightweight, she didn’t think that her focus on ounce-cutting features and high-tech fabrics would win over the audience she set out to reach. Nor did he expect the ultralight community – very online and very male – to provide the kind of grassroots promotion that other ultralight brands benefit from.
Instead, he has taken a different approach. For one, her message to potential customers revolves around simplicity, minimalism, and comfort rather than “going ultralight.” Because of that, she’s already attracting a broad customer base—not just ultralighters and thru-hikers, but also day hikers, peak-baggers, and hikers. She’s also changing the direct-to-consumer sales model that most ultralight brands prefer to stay lean and increase margins, and exploring wholesalers and retailers. Even though sales of Symbiosis gear currently number in the hundreds rather than thousands, the Aspen is already available in 16 retail stores in the US. In comparison, ultralight mainstay ULA lists only 12 US retailers for its products. Most budding ultralight brands choose to exit retail altogether.
Aspen’s design itself also reflects Berkeley’s pursuit of broad appeal. At 25 ounces, it’s quite sturdy for an ultralight pack, using 420-denier Extrema nylon. It also features a full mesh back panel and a UHMWPE mesh front pocket, which reduces weight as well as adds durability and comfort. Additional gear loops, a stretch bottom pocket and oversized side pockets are designed to make the Aspen as versatile as possible.

This year, Berkley is focusing on expanding the product line. Upcoming releases include a larger, framed pack and more size options for the Aspen. The most recent drop is a combination hipbelt pocket/sling bag they’ve named huckleberry. Long term, Berkley isn’t entirely sure where the brand is headed. Double up on an ultralight pack? Or embrace a broader audience with more traditional gear?
“I’m building it very organically and seeing how people respond,” Berkley says. “Whatever comes next starts with listening to women.”
