The ULA Ultra Nexus is a 40L streamlined frameless backpack that weighs 19 oz and is designed to carry 20-25 lb loads. It has five open pockets instead of the three found on most ultralight backpacks, so you can carry all the gear, clothing, and food you’d need on the outside of your pack without needing to stop and open the closed storage in the pack’s main compartment. It’s also the first entirely new pack that ULA has launched in many years, so you should expect some changes to it based on customer feedback. I have a few suggestions below for minor changes that I feel would make the pack much easier to use.

• Type: Frameless
• Volume 40L (32L closed volume)
• Pockets: 5 external and open; 2 closed on hipbelt
• Access: Roll-top closure
• Material: Ultra 200
• Hydration compatible: No ports, no center suspension point inside
• Waterproof: Not seam-taped
• Load lifters: No
• Hip belt: Optional
• Canister compatibility: BV450 fits horizontally, but barrels significantly
• Pros: Durable fabric, great external storage
• Cons: Main compartment barrels easily, no side compression/lash points, extra-long Y strap is ungainly

Two Models Available

The Nexus 40 is available in two different fabrics: the Ultra X Nexus 40 reviewed here is made with Ultra X 200 fabric, which is highly abrasion-resistant. While the Ultra X 200 fabric is itself waterproof, ULA doesn’t seam tape the packs they make with it, so there’s a chance that the seams will leak if you get caught in the rain. ULA also makes an Ultragrid Nexus, which is just recycled nylon reinforced with Ultra fibers in a ripstop pattern.

The back of the pack is unpadded and gets very sweaty in hot and humid weather

Backpack Storage

The Ultra X Nexus has a main compartment, five external open pockets, and two zippered hip belt pockets. The pack is designed so you’ll carry all the gear and food you need during the day in the pack’s external pockets.

The roll top only buckles closed on top and not along the sides, where you’d get better compression.

Main Compartment

The main compartment is a roll top, but the ends of the roll top clip together, rather than down along the sides of the pack, so you don’t get the compression that you would if the ends were buckled to straps along the side of the pack. There’s also no stiffener at the top of the pack bag, which makes it difficult to roll shut if the contents are bulging out the top and to stay shut without unraveling. Rolltups work a lot better if they have a stiffener at the top, or snaps, magnets, or even velcro to hold the two sides of a rolltop together.

Internally, the main compartment is just a big, open space with a thin foam pad held in place by elastic straps. While the pad is designed to cushion sharp objects inside, it is not stiff enough to prevent the contents from barrelling (rounding) and pressing uncomfortably into your back. Forget trying to carry a bear canister inside the Nexus or overloading the space, because you’ll feel it through the back panel.

The only other features inside the main pack bag are two webbing loops sewn into the top seam where you can hang an accessory pocket, sold separately. The Nexus does not have hydration ports, so there’s no point in hanging a water bladder inside.

The back of the main compartment, facing the wearer and behind the shoulder straps, is Ultra 200 fabric, without any padding or mesh, so it’s right up against your shirt. When the weather is warm and you start to perspire, the Nexus becomes pretty sweaty to carry.

Suggestion: The Nexus would be much more comfortable in hot weather if the back were covered with spacer mesh so you’re not sweating on the Ultra fabric. Alternatively, the internal foam pad could be externalized with pad sleeves, like those found on Gossamer Gear G4-20, or elastic cord like that on the Zpacks Nero and other lower volume ultralight backpacks. An external pad wouldn’t necessarily reduce the barrelling that occurs when you overstuff the Nexus, but having a thicker, more cushioned pad, like a few sections of Thermarest Zlite, would surely help.

Side view: the lower pockets have an elastic cord to prevent bottles from being lost.

Lots of Pockets

There are two (lower) bottle pockets on each side of the pack. The bottom pockets have slanted tops with elastic cords to tighten the top and secure items, making them easy to use with water bottles. However, the front of those pockets is open because the bottom of the shoulder straps terminate inside them, and is a common design feature on all ULA packs. But it means you can’t store smaller items in the bottom pocket lest they fall out. ULA runs the shoulder strap anchor through the front of the pocket to pull the pack closer to your hips.

The upper two pockets on each side are smaller and made with Ultragrid mesh. You can use these pockets to hold snacks, your bathroom/trowel set, or even a small cook system like the Jetboil Zip, which fits nicely.

The long mesh front pocket is great for storing damp items

The pack has a long open mesh pocket on the front with an external elastic cord threaded through tabs on the pocket’s perimeter. The mesh pocket is good for storing a wet water filter or spare folding bottles, food, or clothing, while the elastic cord is suitable for hanging damp clothing that needs to dry.

The hip belt has two zippered pockets that are large enough to store modern smartphones. The pockets are sewn to the hip belt and are not removable.

Compression and External Attachment Points

The Nexus does not have any side compression straps, which severely limit the utility of the pack and make it difficult to carry bulky gear unless you can fit them inside the main pack bag. For instance, while you can carry a pair of short folding z-style trekking poles in the side bottle pockets, I wouldn’t recommend carrying longer telescoping poles in this way, because they’re more apt to fall out without a strap to secure them against the side of the pack. It’s a similar story with Tenkara fishing rods: I pack these in the main packbag, rather than trusting them to the side bottle pockets where they’re bound to fall out without my noticing that they’re gone.

Suggestion: The perimeter of the front mesh pocket has webbing loops to hold an elastic cord. If more webbing loops were added along the side seams of the pack (both front and back), then users could add their own cord/cordlocks to lash long items to the sides of the pack. That would make a big difference. Of course, a real side compression strap, like those on the ULA CDT would be even better. 

The excess webbing in the Nexus Y strap hangs behind you like a tail when you’re hiking.

While the Nexus does have a top Y-strap, it’s just weird and absurdly long. One end of the Y strap is sewn to the pack in a seam above the right shoulder strap. From there, it travels to a plastic ring located just above the front stretch mesh pocket, and then finally to a tri-glide buckle sewn to the seam above the right shoulder strap. So the only place you can tension it is through the tri-glide above your right shoulder. That might be tolerable if the webbing that makes up the Y strap were a reasonable length, but it is 3 feet longer than it needs to be (and hangs behind you as you hike like a tail.) So every time you want to open your pack, you have to thread the 3 feet of strap through the right triglide, which is super annoying. Other manufacturers use buckles that you can clip and unclip to access your pack’s top rolltop.

Suggestion: Rework the Y-strap with a buckle above the front mesh pocket that you can unclip to access the roll top. Or give customers the option to use a single strap instead of the Y-strap, like on the ULA Circuit SV.

Backpack Suspension

The Ultra X Nexus is a frameless backpack designed to carry very lightweight loads, maxing out at 20-25 lbs. As such, there’s no weight transfer onto the hipbelt, whose only functional contribution is to hold the pack closer to your torso and to provide a mounting point for the two hipbelt pockets. It should be noted that the Nexus hipbelt is not like the hipbelt used on ULA’s larger packs; it only has one tier of tension with a central buckle and not two. You can instruct ULA to leave the hipbelt off that pack, and I’d recommend doing that. I found it annoying, and with a max load of 25 pounds, a hipbelt isn’t really necessary.

I use folding poles when I hike with the Nexus because it’s difficult to secure telescoping poles to the side of the pack without a compression strap.

Assessement

The ULA Ultra X Nexus is the company’s first new backpack model in quite some time, and while it’s usable, I think it could be a lot more versatile with the changes I suggest above. If you want a frameless backpack that has side rolltop straps, a cushioned and porous back, and a better Y-strap, I suggest you take a hard look at the ULA Photon (35L) or the ULA CDT (50L) instead. They’re both great packs, and I can’t understand why ULA didn’t leverage their designs when they came out with the Nexus.

Disclosure: ULA donated a Nexus backpack for review. 

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