Bottom Line
The Hyperlite Unbound 40 is the #1 pick from our guide to our favorite ultralight backpacks due to its exceptional waterproofness, durable construction, and thoughtful on-trail functionality.
The inherently weather-resistant Dyneema Composite Hybrid fabric and taped seams kept our gear bone dry even after extensive water exposure tests. The Unbound’s simple yet effective suspension system comfortably carried loads of up to 40 pounds during our testing in the Rocky Mountains.
We love the unique organization features, such as the split front mesh pocket, roomy side pockets, hefty hipbelt pockets, and an innovative bottom pocket with trash port access. However, the thin shoulder strap padding and slick back panel may not be ideal for those who prioritize plush cushioning and maximum airflow.
While the Unbound 40 is on the pricey side, its top-tier materials and meticulous construction offer excellent long-term value, particularly for dedicated ultralight backpackers who frequent harsh conditions and log serious trail mileage.
Quick Specs
Hyperlite Mountain Gear Unbound 40
Best Ultralight Backpack Overall
CleverHiker Rating: 4.9/5.0
Price: $369
Weight: 1 lb. 13.6 oz.
Volume: 40 L
Max Weight Rec.: 40 lbs
Pros
- Waterproof
- Durable
- Good organization
- Stable
Cons
- Thinner padding than others
- Flimsy side straps
comfort
The Unbound 40 might not look very comfortable at first glance, with its lack of ample cushioning and mesh back panels, but its sheer simplicity is actually its main comfort feature. Overbuilt packs that make you feel like you’re strapped into a rollercoaster seat with their sturdy hip belts and overly padded shoulder straps can often cause unexpected hot spots or pack rash.
The Unbound (and all HMG packs) features nothing on its back panel but an integrated plastic sheet with a high-density quarter-inch foam backing. This slick, non-abrasive back sheet glides freely across your body without causing much friction.
The frame, which consists of a simple, contoured aluminum stay, transfers weight to the hips exceptionally well. Hyperlite achieves a surprisingly stable and balanced carry without needing load lifters or an overbuilt hipbelt. During our testing, this pack handled loads of up to 40 pounds with ease.
Despite the effectiveness of the simple suspension system, we wouldn’t mind seeing a little more padding on the shoulder straps. Also, although there is some arch to the frame, it doesn’t have the airflow of some other packs nor the moisture absorption of an exposed foam back panel, so accumulated back sweat is noticeable.
Functionality
The Unbound 40 is packed full of handy features for the on-trail backpacker, although it lacks an ice axe loop. The pack includes standard features such as a roll-top enclosure with a lengthy top Y-strap and elastic (although somewhat flimsy) side straps. The hipbelt pockets and side pockets are all roomy and easy to access.
The front panel and bottom are where things get interesting. The split mesh pocket on the front has two access points, the bottom of which is ideal for reaching small items that have sunk to the bottom of the pocket or storing things like a spork, tent stakes, or trowel in their own designated area.
The Unbound also features the increasingly popular bottom stretch pocket with an included trash port. After hiking extensively with this feature, one of our gear analysts has sworn loyalty to it and will never hike without a bottom pocket again.
The final notable feature of the Unbound 40 is the copious amounts of daisy chains. If you like clipping gear to the outside of your pack, this is the one for you, and it makes up for the lack of an ice axe loop.
Water Resistance
The Unbound is one of the most water-resistant ultralight packs that we tested. Even after a serious drenching, the pack’s contents unsurprisingly emerged dry as a bone.
The pack’s Dyneema Composite Hybrid (DCH) fabric is inherently extremely water resistant, eliminating the need for a Durable Water Repellent treatment or polyurethane coating. Additionally, each vertical side seam and sewn-on pack feature is taped to further enhance water resistance. The bound vertical seams cut down on seam bunching, making taping more efficient and effective.
Although total waterproofing can never be guaranteed, and it’s always a good idea to use a pack liner, we strongly recommend any Hyperlite pack for adventures in relentlessly wet conditions.
Construction
Like all Hyperlite packs, the Unbound 40 excels at durability and construction. We’ve encountered countless trail-worn Hyperlite packs with thousands upon thousands of miles on them, and although they are dirty, their construction seems all but bulletproof.
The Unbound takes Hyperlite’s solid construction to the next level with webbing-reinforced seams. The front and bottom mesh pockets—a common weak point for most packs—are made from ultra-durable Dyneema mesh.
The minor downside to the Unbound’s superior structural integrity is the added weight. Its weight-to-capacity ratio is 0.7 ounces per liter, which is heavy for an ultralight pack but much lighter than traditional packs.
The Unbound is available in two fabric versions – a white, 50-denier, and black 150-denier version. For maximum durability, go with the black version.
Should You Buy The Hyperlite Mountain Gear Unbound 40 Ultralight Backpack?
The Unbound 40 is an excellent choice for backpackers who prioritize gear access and organization, superior water resistance, and serious durability.
This pack particularly excels for adventures in relentlessly wet conditions, thanks to its use of highly water-resistant DCH fabric and taped seams. The split mesh front pocket and bottom ‘trash’ pocket are unique features that enhance on-trail efficiency.
The suspension system transfers weight exceptionally well for a minimalist pack despite the moderately padded shoulder straps and hipbelt. However, hikers who prefer maximum airflow against their back may want to consider packs with more breathable back panels.
The Unbound 40 is a significant investment, but its cutting-edge materials and bombproof construction create long-term value, especially for those who log a lot of trail miles or frequently venture into rugged conditions.
Budget backpackers who don’t need the ultimate weather protection and durability can likely find a suitable alternative for a lower cost. But for the serious ultralight backpacker seeking a functional, weatherproof, and extremely durable pack, the premium price of the Unbound 40 will be well worth it.
What Other Ultralight Backpacks Should You Consider?
The Hyperlite Unbound 40 isn’t the only pack we love – check out our full list of favorites!
Hyperlite Southwest 55 Review: For those seeking even more minimalism and a bit of cost savings, the Southwest 55 is a great alternative. It’s built by the same company but features pockets that favor size over quantity.
Atom Packs The Pulse EP50 Review: The Pulse is a strong contender against the Unbound 40. It has similar features (like Dyneema mesh and a bottom trash pocket), exceptional construction, and water resistance. We also love the addition of shoulder strap pockets.
Zpacks Arc Haul Ultra 60 Review: This pack has incredible construction with more permanent waterproofing via its Ultra fabric construction and laminated waterproof backing. Cutting-edge materials meet incredibly lightweight durability with the Arc Haul Ultra.
