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ULA Backpacks: How to Choose

ULA Ultralight Backpacks - How to Choose
ULA Ultralight Backpacks – How to Choose

(ULA) is one of the oldest and most respected ultralight backpacking gear manufacturers. Their backpacks are quite popular with long distance backpackers and weekend warriors in the United States and are a frequent sight along our National Scenic Trails and in the backcountry.

I like ULA’s backpacks because they’re very durable and can be configured to fit a wide range of people, including men and women. In fact, nearly half of ULA’s customers buy backpacks configured for female customers, far more than any other ultralight backpacking manufacturer. They’re also the only backpack manufacturer to offer female friendly S-shaped shoulder straps as an option on every overnight backpack they make.

All of ULA’s backpacks are sewn in the United States if that’s important to you, which also gives them the ability to customize their packs for a small fee. They also provide fantastic custom support in my experience, especially when it comes to making sure that you get a pack that fits properly.

If you’ve never purchased an ultralight backpack before or aren’t familiar with ULA’s product line, it can be challenging to figure out which ULA backpack is right for you. Here are some tips to help you with the selection process, so you get the right pack for your needs.

ULA Circuit Backpack

ULA Circuit Backpack
ULA Circuit Backpack

is ULA’s most popular backpack and the one I recommend most often to hikers looking for a pack that’s durable enough to withstand a thru-hike but lightweight enough for weekend use. With 68 liters of capacity, the ULA Circuit can hold a lot of gear, but has a surprisingly nimble feel and won’t slow you down. It’s also easy to configure for a different types of trips, terrain, and equipment needs, and is burly enough for winter use, so you can use it year-round.

  • 68 liters of capacity (total, including pockets)
  • Weight: 36-41 oz, depending on optional components used
  • Max load: 30-35 pounds
  • Bear canister compatible: a BV500 fits vertically inside
  • Replaceable hip belt with big pockets and multiple sizes available for a custom fit
  • Multiple shoulder strap options available, including female specific straps

Most of the Circuit’s storage is in the main compartment which closes with a roll top, making it easy to pack and access the gear stored inside. Roll top closures provide excellent top compression for larger loads without much added weight, which is why they’re so popular on ultralight backpacks.

The Circuit is organized like most ultralight backpacks with two open side pockets, a large rear mesh pocket, and a hip belt with two large zippered pockets. This design lets you keep the daytime gear you need on the outside of pack, so you can avoid having to stop and dig around in your pack whenever you need something.

The ULA Circuit has a three-part frame the includes an aluminum frame stay, a plastic stiffening sheet, and a foam pad. The advantage of a frame stay is that you can bend it to fit your back and personalize the fit. Load transfer to the hips is very good and the pack is comfortable with up to 35 pound loads.

Read my review of ULA Circuit Backpack

ULA Catalyst Backpack

ULA Catalyst Backpack
ULA Catalyst Backpack

is ULA’s largest capacity pack with 75 liters of capacity and a max recommended load of 40 pounds. While the Catalyst looks quite similar to the ULA Circuit and can be used for thru-hikes, this pack is best used on expedition trips that require carrying more food between resupply points than thru-hikes. The Catalyst is also a good backpack for professional guides or trip leaders because it has extra space for larger first aid kits and technical equipment.

  • 75 liters of capacity (total, including pockets)
  • Weight: 44-48 oz, depending on optional components used
  • Max load: 40 pounds
  • Bear canister compatible: a BV500 fits vertically and horizontally inside
  • Replaceable hip belt with big pockets and multiple sizes available for a custom fit
  • Multiple shoulder strap options available, including female-specific straps

The ULA Catalyst has a much burlier frame system which gives it a slightly less nimble feel than the Circuit. It has two aluminum frames stays instead of one, in part because the Catalyst has a wider and larger pack bag. Having the two aluminum stays means that you can carry much heavier loads with the Catalyst than another of ULA’s other backpacks (other than the Epic and Camino 2 which are also built on top of the Catalyst frame system.)

Read my review of ULA Catalyst Backpack

ULA Ohm 2.0 Backpack

ULA Ohm 2.0 Backpack
ULA Ohm 2.0 Backpack

has a minimalist frame and suspension system that best used by hikers who’ve already made the transition to less bulking and lightweight gear, not those starting down that road. It’s a great backpack, but it requires a more nuanced packing and gear strategy than the ULA Circuit or Catalyst backpacks, which have much heavier stiffer frames.

  • 63 liters of capacity (total, including pockets)
  • Weight: 27.5-32 oz, depending on optional components used
  • Max load: 25 pounds
  • Bear canister compatible: the smaller BV450 fits inside
  • Replaceable hip belt with big pockets and multiple sizes available for a custom fit
  • Multiple shoulder strap options available, including female-specific straps

The Ohm 2.0 is laid out in like other ultralight backpacks with side water bottle pockets and a rear mesh pocket. While the pack back comes with a draw string closure, a roll top is also available. The side compression system is much more streamlined than on the Circuit or Catalyst and uses cord instead of webbing. However, the Ohm 2.0 also gives you many different attachment points so you can rig up a custom compression/attachment system that fits your exact needs.

The Ohm 2.0 frame has a thin foam back panel and a fiberglass/carbon fiber loop to help the pack bag keeps it’s shape. It’s very fragile however and you should avoid sitting on the Ohm 2.0 or checking it as luggage on an airplane because it can break easily. The pack bag is also narrower than any of ULA’s other backpacks, so it really conforms to your body and moves with you. The Ohm 2.0 is my favorite ULA backpack, but it is easy to overwhelm if you load it up too heavily or have very bulky gear that doesn’t compress well.

Read my review of ULA Ohm 2.0 Backpack

ULA CDT Backpack

ULA CDT Backpack
ULA CDT Backpack

is a classic frameless ultralight backpack, one of the few still available from cottage ultralight gear manufacturers. It’s a streamlined backpack with less closed storage than ULA’s other backpacks, but one a very durable one, with great external storage.

  • 54 liters of capacity (total, including pockets)
  • Weight: 19-24 oz, depending on optional components used
  • Max load: 18 pounds
  • Bear canister compatible: the smaller BV450 fits inside
  • Multiple sizes available for a custom fit
  • Multiple shoulder strap options available, including female-specific straps

While the ULA CDT is technically frameless, it has a foam back panel that prevents packed items from poking you in the back. But the secret sauce that makes the CDT so comfortable to carry is the fact the hip belt is sewn directly to the backpack, so you get a carry that moves when you move, provided you don’t overload the pack with gear and consumables. If you need a pack that can carry more weight than the CDT, I’d recommend choosing the Ohm 2.0 instead.

Read my review of ULA CDT Backpack

Specialty Backpacks

ULA makes a number of specialty backpacks that are quite similar to their other backpacks but are “tuned” to specific uses.

ULA Camino 2 Backpack

ULA Camino Backpack
ULA Camino Backpack

is a panel loading backpack designed for hostel-to-hostel and travel hiking, where luggage like access to your gear and airplane carry-on spec compatibility are the chief requirements. Panel loading backpacks let you unzip the main compartment of a pack from the exterior, much like a suitcase, so you can pull out the gear you need without having to unpack your backpack through the top. They’re super convenient for travel or when you’re sleeping indoors in a hostel and have limited closet space.

  • 75 liters of capacity (total, including pockets)
  • Weight: 52 oz
  • Max load: 40 pounds
  • Bear canister compatible: a BV500 fits vertically and horizontally inside
  • Replaceable hip belt with big pockets and multiple sizes available for a custom fit
  • Multiple shoulder strap options available, including female-specific straps

For all practical purposes the Camino 2 is identical to the ULA Catalyst except it has a different pack style pack bag. The shoulder straps, the hip belt, and the frame system, are all identical, so it can carry up to 40 pound loads comfortably. While the Camino can be used as a top loader since it has a roll top, the back of the pack can be opened by opening a zipper that runs around the perimeter of the rear mesh pocket.

ULA Epic Backpack

ULA Epic Backpack
ULA Epic Backpack (the blue stuff sack containing a packraft strapped to the bottom of the Epic is shown for illustration and is not included with the pack).

is designed for packrafting and canyoneering where you want to be able to store all of your clothing, gear and food in an industrial strength dry bag designed for water sports. Instead of a conventional pack sack, it incorporates a, which is cleverly sandwiched to the backpack frame using compression straps and fabric panels to hold it in place. The Epic also has a mesh rear pocket with a zipper down the middle to store gear you want access to during the day. However, unlike ULA’s other packs, it does not have side water bottle pockets or a hydration sleeve.

  • 30-82 liters of capacity (total, depending on dry sack volume)
  • Weight: 52 oz
  • Max load: 40 pounds
  • Replaceable hip belt with big pockets and multiple sizes available for a custom fit
  • Multiple shoulder strap options available, including female-specific straps

is also built on top of the Catalyst frame, shoulder strap, and hip belt system so it has a max recommended load of 40 pounds. While it does come with a dry bag, you can also use the stripped down frame system to carry other things such as coolers, elk quarters, boxes of food – pretty much anything you can wedge between the frame and compression straps. The Epic isn’t for everyone, but if you need a pack like it, it provides the right level of modularity to fill a wide variety of needs.

ULA Fastpack

ULA Fastpack Backpack
ULA Fastpack

is ULA’s newest and smallest capacity backpack, designed for adventure racing, day hiking, or peak bagging. It doesn’t have a hip belt and features a vest-style shoulder harness instead of the J-shaped and S-shaped shoulder straps used in ULA’s other backpacks.

  • 45 liters of capacity (total, 25L in the main pack bag, 15L in the roll-down extension collar)
  • Weight: 26 oz
  • Max load: 15 pounds

The Fastpack is laid out like an ultralight backpacks with 1 liter side water bottle pockets, a rear mesh pocket, and a roll top. It has a foam back panel like the frameless ULA CDT backpack, but with less capacity. If you’re interested in using the Fastpack for overnight trips, I’d encourage you to way its pros and cons against the CDT which provides a bit more flexibility because it has a higher volume.

Additional Information

Backpack Volume

Many ultralight backpacking companies, including ULA, measure the volume of their backpacks differently than mainstream backpack manufacturers, which is important to know if you are trying to compare the weight-to-volume ratio of a conventional backpack to a  ULA backpack.

When measuring backpack volume, companies like Gregory and Osprey only measure the volume of the closed storage and don’t include the volume of external mesh pockets, pockets without lids, or the added volume of an extension collar in their volume specifications. So if ULA’s backpacks seem large in terms of volume, it’s because they include a lot of storage that other companies don’t count. There is an industry standard for pack volume computations, but almost all of the cottage manufacturers ignore it.

Shoulder Straps

You have the option of selecting J-shaped or S-shaped shoulder straps when purchasing a ULA backpack, on all of their packs except the Fastpack. J-shaped straps are traditionally used on men’s packs and S-shaped straps on women’s packs, although they’re also good for men with athletic builds. S-shaped straps wrap around breasts rather than mash them, which is the key difference between the two. See my article on Women’s Lightweight Backpacks, for more information about S-shaped straps and how they differ from J-Straps.

Separate Hip Belt

When ordering a ULA backpack, you can choose from several hip belt sizes. If you’ve every purchased a pack that only comes with one hip belt size (that doesn’t fit you), you’re in for a treat, because you can get a highly personalized fit with a ULA backpack. If you’re unsure how to size your pack, call ULA support. They’re very experienced and helpful and will help you get a good fit.

Torso Lengths

ULA also offers their packs in a number of different torso lengths, but you can further refine the fit by adjusting the height of the hip belt on their Circuit, Catalyst, Ohm 2.0, Epic, and Camino packs. The hip belt attaches to the backpack through a slot in the lumbar area and is secured in place using velcro. The height of the slot has about 2″ of vertical adjustability to it, so you can raise or lower the hip belt, and reduce or lengthen the torso length of the pack beyond the torso length you purchased. This is good if you’re between sizes or you need to adjust the torso length when carrying big loads. Contact ULA support for more information about this feature and how to adjust it.

Wrap Up

There’s a lot of information in this post, so leave a comment if you have additional questions I can help you answer. And do consider if you have questions. Those guys and gals can talk about backpacks all day.

Editor's note: Help support this site by making your next gear purchase through one of the links above. Click a link, buy what you need, and the seller will contribute a portion of the purchase price to support SectionHiker's unsponsored gear reviews, articles, and hiking guides.

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  1. I wish you’d written this before I bought my Circuit, but I would have bought my Circuit anyway (just with much less concern that I’d gotten the right back).

  2. Philip, how’s that Fastpack feel when you break its weight limit?

    Here’s my problem: we do long day hikes in the desert, so I have a need for relatively tiny volume, but higher weight capacity (think a fleece, 12 lbs water and 2 lbs food, so like 20 liters, but also 18 lbs). I’ve been using my “briefcase” (an old Mountain Hardwear 32l day pack that I carry to work every day), but it’s pretty uncomfortable once you get over 15 lbs (which isn’t hard since it weighs like 50 oz all by itself).

    I’m not really looking to save weight, just get something that cinches down comfortably with a small, high-density load.

    • I wouldn’t recommend doing that….all 30 lbs will be on your shoulders.
      I’d get something with a real frame, not just stays. That much water is very dense weight.
      As you say – has to be low volume and have lots of compression. I can’t think of anything that really fits that description except gasp…an Exos 38.

      It has a frame and you can probably take off the lid.

      • I agree with Philip, here. With that much water, the extra ounces spent on a frame will pay for itself each mile. My experience with frameless packs taught me to be careful with route planning, and stay close to water sources so I could avoid carrying more than a liter or two. And even then…I felt that the comfort gain that a frame provided was worth the weight. But that’s me…

  3. You’ve mentioned on a few occasions that cottage manufacturers don’t conform to the capacity measurement standards that the big guys use. Just for comparison’s sake, if I’m looking at the Circuit, ULA says its main compartment plus extension collar is 2800 CI/46 liters. Does that mean it’d be most comparable to, for example, an Osprey Exos 48? Since as you say above an Osprey volume measurement is only the main compartment (and the top lid maybe?)? Does that seem like a reasonable comparison?

    I really want to support these types of manufacturers (and have to some degree, the pack is the only piece of gear i haven’t upgraded to something lighter yet, for a variety of reasons), but it’s tough to compare and get eyes/hands on a product, and I’m reluctant because I’m not confident in the capacity measurements or the sturdiness of the frames. I’m in Arizona and so spend a lot of time in dry conditions where water is sometimes hard to come by, so I tend to err on the side of carrying a lot which, as you noted in your response above, gets very heavy pretty fast.

  4. How do those straps on the fastpack feel? The extra storage at your fingertips sounds intriguing.

  5. Phillip, this is another great article. Also, your website is awesome. It quickly had become my go to site for all info backpacking related. Great job!

  6. Philip, great job as usual. Very helpful. But, I’m still in a quandary about a pack for my twenty-something daughter, who asked for, and “got” a pack for Christmas. We are still in the selection process. She is not yet UL-oriented, but her dad is moving in that direction, slowly, and she is a step behind. I am predicting that she will do a fair amount of 2-3 day trips in the Colorado mountains+ in the coming years and knowing her will get interested in further ULifying/simplifying her gear. She’s not sold on the “REI options,” including that many of them are heavy and complicated with features.

    That said, I got some good advice about making my pack choice one of the last steps in going UL. But I have time — I have a pack that works okay (a Deuter ACT Lite 45). But she needs a pack now! She has nothing….

    The Circuit looks like it might be a good option. Thoughts?

  7. REI and amazon do not sell ULA backpacks, where can i get them in California? thanks!!

  8. I ordered a ULA Circuit pack based primarily on an endorsement. I liked the look of the original green and was ready to love it. I never did. Although ULA is helpful with trying to get the right size to the customer, the pack never felt right due to the shoulder harness. The hip belt was comfortable and fine. I did not like how the lower part of the pack was rubbing against my lower back. My wife looked at the set up of the pack and said “You are not going to like it.” She was correct. My son purchased an Osprey Exos for the same trip. When I compared the comfort, features and overall utility of the two packs side by side, there was no doubt he had the better option. When I had all the gear and food ready to go and began packing, the Exos had a lot more utility. I didn’t like the top closure on the Circuit. The Exos had so much capacity in the top flap. The mesh suspension on the back of the Exos seemed preferable. The side pockets of the Circuit
    seemed shallow and hard to use. I particularly disliked the hard mesh back pocket on the Circuit. The only thing I liked about the Circuit were the belt storage pockets. Two days before departure, I woke up and realized I had to find a different pack. I went to REI, got fitted, compared all the packs they had and selected an Osprey Atmos. I returned the ULA pack and had to pay the return postage. They claimed I had not included the “hand loops”, delayed my refund and charged me $5 for what must be the most useless item imaginable. Trust me, I did not want their hand loops. When I disputed this, they gave me snark about returning the pack a few days outside their 30 day policy. I found this statement on the ULA website. “We may provide Personal Information to third parties or marketers for their marketing purposes.” Gee, thanks?

    • I guess it didn’t fit and you didn’t abide by their return policy.

    • I have a ULA CDT and it is the most comfortable pack I own. I also have a North Face pack and an Osprey pack. I think there may have been something wrong with the way you loaded the ULA pack, as ULA packs have to be loaded a certain way (see Erik the Black). Once you get the hang of loading them right, they’re great. They are designed for lighter loads, although I’ve had my CDT up to 25 lbs and still it was comfortable. The hand straps, by the way, are useful on long treks when you want to take some weight off your shoulders. I remove everything else from the CDT except the hand straps. My weight for a large is 20 ounces.

  9. Nice comparison review, Philip. It can be difficult to sort through the options on a vendor’s site, especially when you can’t physically check them out, like with the cottage manufacturers. The Catalyst is my go-to bag for long distance hikes. It’s very comfortable, even with 5 or 6 days worth of food. I’ve also had great customer service from ULA. Once on a scout trip, a scout running through camp tripped on the shoulder strap and ripped it apart at the base. I sent it back to ULA for repair, and they fixed it plus sent it back to me for no charge. A Circuit is on my wish list for trips where I don’t need the extra space for colder weather gear.

  10. Phillip,

    Big fan of ULA. I’ve had an Ohm 2.0 for 3 years now, best pack I’ve ever owned. Every design feature makes sense. It’s the best “generalist” UL pack in my opinion—not too heavy or big, but not tiny and frameless.

    Also love your website, glad you are still keeping things running. Love your top-10 lists!!

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