Drop 4.4 oz from the ULA Catalyst in 5 minutes

In five minutes, 4.4 ounces of extraneous items can be easily removed from the Catalyst and other ULA packs.

For 5- and 7-day guided trips this summer in the Brooks Range and Yosemite National Park, I plan to carry (and review afterwards) the ULA Catalyst. Its key specs:

  • 48 oz (3 lbs 0 oz, 1360 grams)
  • 4,600 cubic inches (75L)
  • Twin aluminum stays
  • Durable fabrics throughout
  • Generous hipbelt pockets and front stash pocket
  • Made in USA
  • $280
  • More information

ULA appropriately describes the Catalyst as “the tried and true workhorse of [our] pack line.” Most of its features trickle down to the smaller 41-oz Circuit, which honestly is a better pick for most 3-season trips — I need more volume and load support when I’m guiding than when I’m on a private trip.

Strip it down

Many backpacks include extraneous features and materials, leaving open the opportunity to shed weight by taking scissors to it. This is not the most effective weight-savings tactic, but it’s usually worth a Snickers bar.

I wish that products arrived exactly as I want them, but I understand the manufacturer’s rationale for including these extra items: if its products lack features or functionality that a large number of prospective customers want or expect, it sales will be hindered.

With the Catalyst (and with ULA’s other packs like the Circuit, Ohm, and CDT), the weight-savings potential is greater than with most other packs. I easily removed 4.4 ounces (125 grams), which amounts to a 9 percent weight reduction.

The process is easy, too. It took me just five minutes. And everything is reversible — by reattaching webbing clips and/or cord locks, the functionality could be fully restored.

A word of caution: to remove the cord cinches, you will need to use a knife to gently pry them open. So that you don’t stab yourself, I recommend holding the cinches with pliers, not your fingers.

Total weight savings is 4.4 ounces, or 9 percent of the pack’s spec weight.

Save 4.4 ounces in 5 minutes

I removed six features that cumulatively weighed 4.4 ounces (125 grams), listed below. Interestingly, the weight-savings were greater when I first did this seven years ago — in 2012 I managed to remove only 3.8 ounces.

  1. Hydration sleeve,
  2. Internal accessory pocket,
  3. Bungee cord over the front stash pocket,
  4. Two bottle holsters on the shoulder straps,
  5. Two handloops, and,
  6. Two ice axe attachments.

The hydration sleeve (1.0 oz) is useless to me since I use water bottles, not a reservoir-and-tube system.

The internal accessory pocket (0.6 oz) could fit small items like toiletries, a headlamp, and Aquamira. But I prefer to keep oft-needed items in the hipbelt and side pockets. And I like to keep other small odds-and-ends in a free-floating stuff sack, which is more portable and won’t get caught up with items being shoved into or removed from my pack.

Water bottle holsters (0.7 oz) are attached to each shoulder strap, and best fit 20-oz squeeze bottles like those used by cyclists and ultra runners. But I normally use a 1-liter smartwater bottle, and I like to keep it in my left side pocket, where it’s out of the way but still easily reachable.

Handloops (0.8 oz) dangle from the shoulder straps, too. If you don’t use trekking poles, they are a nice place to hang your hands to avoid the pooling of blood. But I always use trekking poles, so I will never miss the handloops.

A bungee cord (0.5 oz) is threaded over the front stash pocket, and could be used to secure items to the pack’s exterior, like a rain jacket or a mid-layer fleece. But the mesh pocket serves the same function and is more secure; and the bungee is snag-prone when hiking off-trail through brush.

The ice axe loop attachments (0.4 oz) are convenient for carrying an axe, but relatively few hikers ever have to. Prior to my trips in Yosemite, which had an epic 2018-19 winter, this is the one feature that I will reinstall.

Questions about the ULA Catalyst? Leave a comment.

This post was originally published on July 24, 2012.

Disclosure. I strive to offer field-tested and trustworthy information, insights, and advice. I have no financial affiliations with or interests in any brands or products, and I do not publish sponsored content

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Posted in on June 6, 2019


  1. Paul Mags on July 24, 2012 at 2:06 pm

    Oddly (or not?) stripping the pack is one of the first things I did when I bought it. Love how ULA allows the pack to be very customizable and can shave off excess weight easily. More than the weight savings, it is the philosophy “If I don’t need it, why take it?”. Applies not just to packs, but other parts of life, too!

    • Unnamedpeaks on June 7, 2019 at 7:34 am

      Will you share your thought process (maybe add to article) of deciding which pack to use for these trips?

      Why using this as opposed to
      – Flex capacitor (too small?)
      – Hanchor Marble (since you like the Marl so much…)
      – Ospret Aether Pro (which you recently gave such high praise and seems to be same size)


      • Andrew Skurka on June 7, 2019 at 8:30 am

        These are all good packs, but they excel in slightly different applications:

        Osprey Aether Pro would be my pick for multi-week trips in the Brooks, or maybe week-ish long with a packraft. High-density food load and packraft, plus quite a bit of base weight.

        Flex Capacitor is great for 5-14 day trips. Many of the clients will be carrying one.

        Catalyst has a little bit more volume than the Flex. So perhaps more of a guide pack, or the pack for the person in the group who will be carrying a disproportionate amount of the shared gear. And a great winter pack.

        Hanchor Marl is a great 3-10 day pack. Smaller volume, still good load support.

  2. Chad "Stick" Poindexter on July 24, 2012 at 3:08 pm

    I have the Circuit, but the first thing I did when I got it was to remove the hand loops, the inner mesh pocket and the hydration sleeve. I left the shock cord on the front, but I don’t see why it should stay… Next time I take it out I will consider removing it…

    I agree with Paul though, I love the ULA packs. They are great packs, but the fact that everything can be removed in such a way that it can be (easily) added back later on if so desired is really nice. Nothing worse than buying a new pack, permanently removing things and then wishing you hadn’t later on… (thankfully though, I have not done this). I think it is always better to use the pack as delivered for a bit before removing the things that cannot be (easily) reattached.

  3. Philip Werner on July 26, 2012 at 8:33 am

    I bought a Catalyst this year for guiding because of the higher capacity and removed everything you removed the second I unpacked it.

    How do you like their roll top? Mine keeps unraveling and opening when the pack is full. PITA.

  4. Trevor Guthrie on July 28, 2012 at 8:05 pm

    Personally with the exception of the hydration sleeve I have left all of these attachments intact. I don’t use trekking poles so the hand loops are very nice. The water bottle holders I use with 20 oz plastic coke type bottles or smart water bottles I love the easy access with out all the BS of a hydration sleeve. And the internal pocket is where I stash my keys and wallet so they don’t bug me when I’m hiking. I’ve had my catalyst for 4 years and I and totally happy with it and the options is actually one of the things I like the most.

  5. Kathy RedHat on July 31, 2012 at 12:47 pm

    I own three ULA packs: Catalyst, Circuit, and CDT. As my loads have gotten lighter, I use the Catalyst less and less. But ULA makes the best packs out there, in my opinion. I, too, strip some unnecessaries, but I do love the water bottle holders.

  6. Warren Isbister on July 31, 2012 at 3:02 pm

    I love the way ULA packs arrive. Plenty of removable options that you can easily remove, but also, replace just as easy as removal, should you come to a time when you do end up wanting them. We’ve used the bungee cords to suspend tarps. The water bottle holsters can hold a rolled up map, umbrella, hiking poles, not just water. The mini pocket easily flips out of the way to avoid snagging things while loading.

  7. Jeremy Young on August 4, 2012 at 6:59 am

    Andrew, this pack is obviously designed to be able to remove these features to customize the pack and save weight. But, in your book, you recommend cutting out these similar features of packs like the GoLite Jam which are actually sewn in. Doesn’t cutting out large pieces of fabric from these packs reduce the structural integrity of the entire pack? I haven’t bought a lightweight pack yet. I am still making the rest of my other gear decisions. I was just wondering.

    Love your book by the way. You did an excellent job on it. I will refer to it often.

    • Andrew Skurka on August 4, 2012 at 8:04 am

      > Doesn’t cutting out large pieces of fabric from these packs reduce the structural integrity of the entire pack?

      Possibly, depending on what you cut out. In the case of the GoLite Jam series, the biggest weight-saving technique is to remove the hydration sleeve and foam back pad (plus its housing). I haven’t noticed any structural effects from this. Smaller actions like shortening waist belt webbing poses no problem at all.

  8. Jeff on September 30, 2012 at 1:53 pm

    Hi Andrew,

    I was looking at getting the ULA Catalyst because I take a lot of trips where a bear canister is required. I have also read good things about the ULA Circuit. I read the Circuit only carries a bear can vertically (or horizontally at the top of the pack).

    Have you had any experience with the ULA Circuit? Any recommendation of one over the other? What pack do you use when you’re solo (not guiding) and a bear can is required, would you still take a pack like the Catalyst, or something smaller like the Circuit or even the ULA OHM?

    More info about me:

    Base weight: 11-12lbs
    Average trip:3-7days
    Hike a lot in areas where bear can is required
    Looking to lighten up more

    Any help would be great!


    • Andrew Skurka on October 9, 2012 at 12:28 pm

      I have not used the Circuit, only the Catalyst. If I were traveling solo in average 3-season Lower 48 conditions, the Catalyst would probably max out on a 1.5-2 week stretch between resupplies. On my most recent guided trips in Yosemite, I loaded the Catalyst with my personal gear, 7 days of food, group supplies (first aid, repair, communications), and a BV 500 canister; I lined its inside with my torso-length foam pad too. It was near its max, though not at it.

      If you still have questions about the packs, I’d recommend that you call ULA. They’d be happy to walk you through the decision-making process.

      • Jeff on November 1, 2012 at 8:45 pm

        Thanks for your reply Andrew. I ended up getting the Catalyst for Yosemite trips and I plan on doing a JMT through hike next summer, should be the perfect pack for that. I ended up going with the OHM for all other trips where I don’t need to carry the darn bear can.

        I ordered a large, but I’m right on the border of sizes with a 20.5 in torso. I usually size up in this case, but I read in your book (Ultimate Hikers guide) that you recommend sizing down, so all the weight is above the hips. This makes sense, so I ordered the medium to compare. It’s still on it’s way, so I’ll have to get back to you on that.

        BTW: I did trip the extras off the packs, so thanks for the tip!

        • Lange on June 8, 2019 at 7:36 am

          Jeff, I made it through the JMT in 2017 with an Ohm, although it was well beyond its comfort weight a couple times. I also had to use an unconventional approach for the bear can: I kept my food in a dry bag during the day and stuffed my sleeping bag in the canister so I could strap it to the top of the pack without being off balance. Soon as I set up at camp I swapped my food back into the canister. It was a little beyond its service range in hindsight, but not by much (and was very comfortable with 3-4 days of food).

  9. Chris on October 13, 2012 at 7:25 am

    Could be a silly question — in the actual process of removing the water bottle holsters what was the trick to undoing the small black pull tabs that affix them? The cord locks are a no brainier, but I want to preserve the black tabs and haven’t had luck with a screwdriver prying them open. Probably just being too gentle! Have the Circuit, but the same accessories apply and I find most of them superfluous. Doesn’t sound like it, but do you make any modifications to the Catalyst’s hipbelt?

    • Andrew Skurka on October 13, 2012 at 8:56 pm

      To remove the water bottle holsters without cutting the bungee cord, you need to pry apart the end-lock with a knife.

      I haven’t made any modifications to the hip belt.

  10. Stuart on October 25, 2012 at 9:05 am

    After three months, what are your thoughts about the Catalyst? Has it met your expectations? Any particular likes or dislikes? Having tried and failed to get on with a couple of frameless packs, I’m looking at the Catalyst as a pack for winter trips between 2-5 days in duration in the CO high country, and for next spring/summer as I introduce my young son to the joys of backpacking, most likely hauling most of his kit too. Until recently I thought something as large and heavy as the Catalyst would be a step in the wrong direction. Your ‘stupid light’ essay resonated with me and the pack seems to be the category I’ve had the most challenges with. Thanks in advance Andrew.

    • Andrew Skurka on October 25, 2012 at 11:06 am

      Overall, very solid pack. I’d like to see a few changes — e.g. swap out mesh back pocket for woven nylon, replace roll-top closure with drawstring-style, eliminate the mesh back panel because it collects pine needles — but in the scheme of things they are small criticisms. It carries weight well, it’s a good size, it’s durable, and it has nice features (e.g. waist belt pockets, pull cords on side pockets, etc.). It’s become my go-to packs for guided trips, and for personal trips where I’m carrying a heavier load (e.g. bear canister and a week’s worth of food), assuming I don’t need a packraft, in which case I revert back to the EPIC.

      • Jeremy on October 29, 2012 at 10:02 pm

        So, the ULA Catalyst has become your new go-to pack? Why do you prefer it over your previous go-to pack, the GoLite Jam? I’m shopping for a lightweight pack and I have it narrowed down to a ULA pack or the GoLite Jam. I’m just looking for all the info I can get before making a decision.

        • Andrew Skurka on October 29, 2012 at 10:25 pm

          The Jam 50 and Catalyst are very different packs. The Jam 50 is better for smaller and lighter loads (less than about 25 pounds, maybe up to 30 if you have a lot of water). The Catalyst is better for larger and heavier loads. If you are looking for a do-it-all pack, I’d go with the Catalyst since I’d rather carry ~one extra pound in unnecessary load-carrying capacity than to be missing it.

  11. Daniel Allen on October 29, 2012 at 11:34 pm


    what do you think of the catalyst as a winter pack? would it do ok with snowshoes and a shovel, for example, and maybe accommodate 2 closed cell foam pads (one internal, like the CDT, and another on top)?

    Thanks for any input!

    • Andrew Skurka on October 30, 2012 at 8:02 am

      The Catalyst would work as a winter pack, but I wouldn’t buy one for that specific purpose. The external mesh pocket is not suitable for winter use, due the need to carry skis, snowshoes, shovel, etc — that pocket will quickly get ripped up, and possibly too the lighter ripstop nylon that constitutes the pack body in this area.

  12. Rich on January 15, 2013 at 12:01 pm

    Hmm. Maybe talk to Chris to make a “ULA Skurka” pack or something? You have been working with those guys for a while now right?

  13. Greg B on April 20, 2013 at 6:26 pm

    When Brian owned ULA a lot of these options were actually options. But I can certainly see how it’s easier to simply include the hydration sleeve etc with all packs. I also removed the hydration sleeve from my pack and I’m tempted to removed the mesh pocket.

    I use the water bottle loops with standard Aquafina 750ml and 1L bottles. One advantage which isn’t immediately noticeable is that when you’re carrying a low base weight and your entire pack weight with food and water is around 20 to 25 pounds then 2 liters of water in front of you counterbalances a large percentage of your pack weight. When you put 20% of your weight in front of you the balance of the pack changes nicely.

    Overall, I absolutely love my ULA Circuit.

    • JustinHB on August 1, 2013 at 1:43 am

      That last comment about the water weight counter balance is something I’ve noticed as well. This is the first time I’ve seen it discussed about any pack, but two full, one liter bottles equals around 4.5 lbs including the bottle itself. I don’t enjoy the bulk on my chest, but my lower back loves it. lol.

      • Dieter on June 3, 2014 at 6:40 pm

        This type of load balancing is the philosophy of Aarn. Have a look at the video https://www.youtube.com/watch?v=E0ioVtcpEQI Hhttp://www.aarnpacks.com/
        Their front packs have a frame to transfer the weight directly on the hipbelts so you can walk upright (even with heavy loads) while with a traditional style backpack you HAVE to bend forward. They are heavier and more complex to put on / take off but the concept is very convincing. I am thinking of buying one of these or the catalyst. Both have good reviews.

        Andrew I would love to hear if you have any opinion about this type of pack.

        • Andrew Skurka on June 3, 2014 at 8:37 pm

          I haven’t used these exact packs. The most similar I used was a front pouch that suspended across the sternum. With a really heavy pack, I could see the benefit of such a system, as it would allow a more upright walking position. Otherwise, however, I think the benefits would be outweighed by the inconveniences, notably having something big in the way up front and then having an extra step in taking off your pack.

  14. Dieter on June 4, 2014 at 6:45 am

    Thanks a lot for your quick reply. I had an interesting experience long time ago with my girlfriend. We shared a frame less pack for a day trip. For her that was uncomfortably heavy to carry while I hardly felt it. For her a pack with a light internal frame and hip belt would have made sense while for me the same pack was extremely comfortable.
    Applying this to the 35lb category I believe that many backpackers in good shape are completely happy with a well made traditional pack. But as I get older and with increasing back issues I think that an Aarn style pack might be a good option for me – even only for a planned 8 day no resupply trip.
    However I will go the beaten track for now and order a catalyst today. But I might try to replace the belt pockets with larger ones.
    Thanks again for your help. Highly appreciated.

  15. Phil on January 5, 2015 at 2:47 pm

    Andrew, I just purchase the ULA Catalyst for an up coming trip to Philmont plus a few shakedown trips. What are you thoughts on shortening the straps on the pack to cut weight? Thanks for your other weight cutting tips.

    • Andrew Skurka on January 5, 2015 at 2:52 pm

      It’s a small weight-savings opportunity. I’d do it more because long straps are annoying.

      To resew the fold at the end of the strap (so that it does not slide through the buckle), I would recommend a Speedy Stitcher Sewing Awl.

  16. Rusty on May 28, 2015 at 12:03 pm

    After all these years and new companies jumping up making lite weight stuff, is this still your go to pack? I have it narrowed down to ULA or Hyperlite……
    Thanks for your opinion

    • Andrew Skurka on May 29, 2015 at 8:08 am

      You’re unlikely to be disappointed with a ULA pack. Ditto if you go with HMG. Lightweight, durable packs with relatively good load-carrying capacity (given their weight).

      My exact go-to pack changes frequently. On my most recent trips, I was testing a new Sierra Designs pack, which will come out if 2017 or perhaps quietly in 2016. On many of my guided trips, I bring the ULA Epic because I can load more stuff in it and on it than other packs. And last summer I was using the ULA Ohm on personal trips.

  17. russ brent on October 20, 2015 at 10:14 am

    I ordered a ULA Circuit pack based primarily on a bloggers 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?

  18. Gordon on February 3, 2016 at 7:14 pm

    I guess we can all find something to complain about.

  19. Adam on June 6, 2019 at 11:38 am

    I’ve used the Catalyst for winter trips several times. It’s decent. The shovel blade fits nicely in the front pocket, and I’ve never had any concerns about the durability of the mesh. The over the top strap can accommodate a closed cell foam pad. Snowshoes can be strapped onto the bungees (I’ve never used skis). The main issue I have is the weight distribution when snowshoes are attached that way. It really pulls you backwards. I wish the over the top strap was V-shaped, so snowshoes could go up there. It also can suck up water, which is a problem for all non-waterproof packs. It gets heavier and then takes quite some time to dry out at home. I’m going to try the Seek Outside Divide for winter now due to that issue. It’s a bit heavier but I think solves quite a few of those issues.

  20. Ross Seymour on June 14, 2019 at 10:15 am

    The internal accessory pocket is the exact size of a Kindle (paperwhite or voyager) so I put it back in.

  21. Bret Russell on July 19, 2019 at 7:47 am

    The first thing I did with my ULA Circuit pack when it arrived was to consider packing it up and send the damn thing back. I was shocked at how much I didn’t like about it. They gave me a hard time when it arrived a day later than the return warranty and they dinged me for a hand strap that they said was missing. It was in a pocket. I was totally happy with the Osprey I bought instead. Marginal product and sub marginal customer support.

  22. John R on November 23, 2020 at 8:50 am

    Hello, Andrew: Do you have any experience or opinions on backpacks made from x-pac material, a composite fabric comprised of multiple layers laminated into a single sheet? I am contemplating purchasing an x-pac Catalyst, second hand with light use. The pack will supplement my Circuit for trips requiring a BV 500. Thanks.

    • Andrew Skurka on November 23, 2020 at 9:17 am

      For nearly all users, the differences between it and ULA’s standard fabric is theoretical — you have to be doing some pretty crazy things to push these fabrics to their limits.

      So, if you fall into 99 percent of users, go for it. And if you’re in that 1 percent, it’s probably still good enough — ULA doesn’t use fabrics that don’t go the distance.

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