ULA Circuit Ultralight Backpack Review

Bottom Line

The ULA Circuit is our favorite load hauler for its large carrying capacity, durable build, and comfortable suspension system. This pack has become a favorite on the Pacific Crest Trail and doesn’t fail to impress even after thousands of miles of use.

Our team has extensively tested the Circuit on thru-hikes of the Pacific Crest Trail and Continental Divide Trail, as well as controlled lab-like settings. Although the water-resistant DWR and PU coatings wear off over time, the ultra-durable 400 robic nylon keeps going and going. The strong webbing straps and nylon-blend mesh front pocket also add to its durability. The Circuit impressively carries huge loads comfortably for an ultralight pack, with a cavernous total volume of 68 liters. The carbon fiber and aluminum frame system, paired with comfy contoured hip and shoulder straps, provides a stable carry for long days on the trail.

The Circuit’s moderate price point is easily justified by its quality and features, but for smaller or more affordable options, check out our full guide of favorite ultralight packs.

comfort

During our testing in the Rocky Mountains with loads up to 34.5 lbs, we found the ULA Circuit delivered a stable and comfortable carry for such a lightweight pack. The robust suspension system provides excellent load transfer to the hips due to its carbon fiber and Delrin hoop frame, dense foam back panel, and single aluminum stay.

The Circuit’s shoulder straps contour well to the body, though they could benefit from a bit more padding. When we pushed the pack near its 35 lb max comfortable load, it began to feel a tad shoulder-heavy.

That said, the Circuit’s array of fit adjustments, including load lifters and dual hipbelt adjusters, allow us to effectively shift and fine-tune the weight distribution between our hips and shoulders throughout long trail days. This adjustability and the padded and moderately breathable mesh back panel keep the pack riding comfortably mile after mile.

We can also reach water bottles and supplies in the side pockets fairly easily while hiking, minimizing frustrating pack-off stops.

Functionality

The ULA Circuit’s standard pocket layout and functional attachment features provide ample storage and organization options. The cavernous main compartment is enclosed with a traditional roll-top and lengthy single top strap that easily accommodates a bear canister.

While the front mesh pocket is stretchy and convenient for stashing rain gear or daily essentials, it could be a little bigger. The side pockets are tall and roomy, each swallowing 2 liters of water bottles with room to spare. 

The hipbelt pockets are generously sized and easy to access. They’re big enough to hold large smartphones and plenty of snacks to fuel the journey. The pack features two ice axe loops (one could be used for trekking poles), each with an elastic attachment at the top of the pack. 

The side compression straps can also be used as a wrap-around for carrying snowshoes or other large items if desired.

Water Resistance

The ULA Circuit offers decent water resistance while not being totally waterproof. During our water exposure test, we noticed some mild dampness inside the pack. There wasn’t a single definitive weak point, but the water resistance gradually gave way over time.

The pack is waterproofed with 3 passes of teflon DWR and 3 passes of PU on top of 400 robic fabric. Because the water resistance comes from a chemical coating rather than a physical barrier, it will need to be re-treated at some point. However, since it has several layers, it lasts quite a while, and our analysts who’ve had this pack for several years and thru-hikes don’t have many complaints in this department and just use a pack liner/cover as needed.

Construction

The ULA Circuit masterfully balances weight and durability for an extremely versatile pack. This balance makes it a popular choice for thru-hikers on the PCT and off-trail backcountry enthusiasts. The weight-to-capacity ratio is an impressive 0.5 ounces per liter.

The main body is constructed of 400-denier robic nylon, making it one of the most durable nylon packs available. Although the water resistance wears off over time, we’ve seen these packs hold up beautifully after thousands of miles on demanding trails.

We were also impressed by the durability of the front mesh pocket, a common failure point on many lightweight packs. ULA’s choice of a heavy-duty mesh blend strikes the right balance of stretch and resilience. It securely holds an array of gear without sagging or tearing.

Finally, while other packs opt for skinny compression straps and outer attachment points, the Circuit utilizes strong webbing. The webbing provides extra security for attaching heavy items like snow shoes or ice cleats.

Should You Buy The ULA Circuit Ultralight Backpack?

The ULA Circuit is an excellent choice for all levels of backpackers and thru-hikers seeking a durable, lightweight pack that can comfortably handle long-distance treks. Its 68-liter capacity and robust suspension system make it well-suited for hauling lots of gear. The features are easy to use and provide plenty of organization options.

The enhanced durability and ample storage capacity aren’t necessary for dialed-in ultralight backpackers or fast packers. Hikers with a miniscule base weight would benefit from a smaller, frameless pack.

In terms of value, the ULA Circuit offers a combination of quality, durability, and performance to justify its price point. The use of premium materials, such as the 400 denier Robic nylon and carbon fiber suspension system, ensures long-lasting reliability and comfort on the trail. For dedicated backpackers who prioritize a lightweight, high-capacity pack that can withstand the rigors of extended adventures, the Circuit is a worthwhile investment.

While there are certainly less expensive options available, ULA’s proven track record instills confidence and reliability for its users.

What Other Ultralight Backpacks Should You Consider?

For the fast-packer or season ultralight thru-hiker, we’ve reviewed smaller and more lightweight packs in our full guide to ultralight packs.

Gossamer Gear Mariposa 60 Review: The Mariposa is a favorite for its comfortable carry and decent capacity. While it’s not quite as durable or water-resistant as the Circuit, it offers luxurious carrying comfort and some unique design features..

Hyperlite Mountain Gear Southwest 55 Review: The Southwest is a minimalist pack that is also available in a 70-liter version. It lacks cushy padding but is supremely durable and weather-resistant.

Zpacks Arc Haul Ultra 60 Review: The Arc Haul Ultra is an efficient gear hauler that prioritizes optimum weather resistance and weight savings. It has a more rigid feel than the Circuit and is tougher on the wallet.