Four miles into the Idaho backcountry, and with two mule deer bucks down, the Exo Mountain Gear K4 pack was about the get a workout. Not only that, but having torn the meniscus in my knee during a September archery elk hunt, I would be lying if I wasn’t a little worried how the bum knee would handle this 120-pound load over four miles and 1,800 vertical feet of descent. After all, climbing was not what was bothering the knee as much as having to go downhill. So, with a tentative and cautious stride, we each loaded a whole bone-in deer and our gear and headed for the truck.
At this point in the season, having packed out several other animals already with this Exo Mountain Gear K4 5000, the one thing I was fairly confident in was that the pack was not going to be the most prominent source of discomfort, and for that I was thankful. That being said, none of the the other packouts exceeded the 100-pound mark or were quite as long as this one.
Scenarios like this are why I wanted to do an Exo Mountain Gear K4 pack review. When the chips are down and the hunt gets real, you need a pack that can handle the load and do it comfortably.
How it was Tested – Exo Mountain Gear K4 5000 Pack Review
When I talked to Steve over at Exo Mountain Gear about this review, he expressed a desire to have an honest review done based on a full hunting season of use. We believe long-term testing is where the real value of a review comes from, and even though Steve and the Exo Mountain Gear crew thoroughly test their packs long before they hit the shelves, I appreciate that they see the value of getting other opinions based on long-term testing.
With that in mind, I set out to put the Exo Mountain Gear K4 5000 to work from the day I got it in May until the very last day of our late season rifle elk hunt which ended December 31st.
It is not hard to “test” a pack on a hunt or two, or even pack a heavy load a few miles, but nothing replaces actual hard use in the field for months on end. I am not talking about just a few hours of heavy loads, but hundreds of hours packing sand on training hikes, miles and miles hauling backcountry gear, and truly heavy loads shuttling wild game meat. How does the pack feel after 100 miles? How about 200 miles? How does it perform after REGULARLY hauling heavy loads? Do any squeaks or discomfort pop up?
That is what we set out to test for, and this pack pounded the trail all summer long on multiple training hikes each and every week (minimum 65-pound loads) and well over 100 mountain miles during the fall archery and rifle hunting seasons.
As hunting season approached, I used this pack to get out and scout/set some trail cameras, which included nice long rides on the dirt bike. Once Aug 30th hit, archery season opened and many miles were put on this pack during two extended weekend trips and one week-long archery elk hunt. The pack even got DRENCHED in an uncharacteristic early September storm. As October rolled around, the pack became a part of my body for a long weekend of rifle mule deer hunting as well as another week-long mule deer hunt.
Finally, our late season elk hunt is a bit different because that particular hunt typically requires the weather to turn nasty before the hunting is any good. The pack accompanied me on two outings for this late season elk hunt.
All told, I lost count of how many miles this pack traveled with me over the course of the various hunting seasons, but it had to be well over 200 miles, including hauling an elk during September archery, my son’s mule deer buck in mid-October, and a four mile, 120-pound load (a full mule deer buck and gear) in late October. Of course, all of the spring and summer training hikes were loaded with a minimum of 65 pounds, so this pack has hauled A LOT of weight over the last eight months.
Specs – Exo Mountain Gear K4 5000 Pack Review
Specs are important but certainly not the most important thing when it comes to packs. Sure, everyone would love to have their pack start as light as possible, but that typically comes with the pack sacrificing its ability to haul heavy loads. Fortunately, all of the Exo Mountain Gear packs shine in the specs department, offering some of the lighter weights you can achieve, particularly given their load-hauling ability.
Make sure to check out our other gear reviews and the Backwoods Pursuit YouTube Channel to help you decide what gear will help you stay out in the field longer.
With that in mind, here are the specs for the Exo Mountain Gear K4 5000 pack that I tested.
| Exo K4 5000 Specs | |
|---|---|
| Fabric | 500D Cordura |
| Frame Material | Carbon stays |
| Foam | Closed-cell foams with cross-linked ethylene copolymer |
| Main Bag Size | 5,010 ci |
| Lid Size | 648 ci |
| Total Capacity (bag & lid) | 5,658 ci |
| Pockets | 11 |
| Buckles | Duraflex |
| Zippers | YKK |
| Weight (Bag, frame, lid, hip belt, shoulder harness) | 5 lbs 13 oz |
| Weight (Bag only) | 2 lbs 6 oz |
| Weight (Frame only) | 2 lbs 15 oz |
| Lumbar Material | Superfabric (600D Polyester base) |
| Shoulder Harness | Spacer Mesh |
Specs are not everything, but it sure is nice when you do not have to sacrifice right off the bat as the Exo Mountain Gear K4 packs are extremely impressive.
Hip Belt – Exo Mountain Gear K4 Pack Review
One of the updates that Exo Mountain Gear made with the new K4 pack was a HUGE upgrade to the hip belt. I was not in love with the hip belt of the Exo K3, although it served me well on many heavy pack outs. That said, room for improvement was there, and the folks at Exo did just that.
MORE RIGID YET COMFORTABLE
One of the first things I noticed is how much more robust the Exo Mountain Gear K4 pack hip belt was than the previous version. Not only did I find that this change provided more support with heavy loads, I also found it to be more comfortable on a day-to-day basis, even without a heavy load. That is saying something as I have typically found that you sacrifice everyday comfort for load hauling comfort.
LASER-CUT MOLLE WEBBING
The new laser cut molle on the outside of the hip belt opens up a world of possibilities with the Exo Mountain Gear K4 pack. While Exo offers a lot of well thought-out accessories of their own, if you are someone who has a favorite Molle attachment from another manufacturer, odds are it will fit on this pack.
As you can see above, I was able to easily fit an Exo Hip Belt Pouch, the new Exo Insulated Nalgene Holder, and my Ivory Holsters custom holster with room for another water bottle holder if I wanted.
LUMBAR PAD
Another area of HUGE improvement over the K3 was the more substantial, significantly more robust lumbar pad. After testing packs over the years that feature a larger, more robust lumbar pad like the Initial Ascent IA4K, I was STOKED to see the new lumbar pad on the K4. The softer foam of the K3 was one of the areas of that I did not love about that model with loads exceeding 100 pounds.
That was far from the case with the more dense foam they used in the Exo K4 lumbar pad. Even after several hundred miles of use for this review, at the end of that four-mile pack with 120 pounds, I never once noticed the lumbar pad compress enough that I felt the frame on my backside (like I did with the K3). The raised texture on the oversized lumbar pad kept the pack perfectly in place, even after that four-mile, 120-pound pack out. I was incredibly impressed.
On the comfort side of things when NOT hauling a heavy load, the foam is the perfect blend of rigidity for heavy pack outs, and soft enough to stay comfortable throughout the day. I never felt like I was giving up comfort for the performance, which is not usually the case.
Harness – Exo Mountain Gear K4 Pack Review
Exo Mountain Gear also updated the harness design of the K4 pack, which again offers more rigidity than the previous K3 pack but still managed to provide excellent comfort. They incorporated more laser cut Molle in the harness for accessories as needed, like the Garmin Mini Pouch. I found this to be useful during the scouting and hunting seasons so I was not digging around in the pack for my Garmin Mini.
Interestingly, I also found the new harness to give me more “pressure” than the previous K3 design with my 65-pound loads. I played with the fit a number of times, but no matter how I adjusted it, I always felt like I was getting a little bit of light pressure pulling my shoulders back. This pressure was not pulling down my shoulders, as in it did not feel like the weight was on my shoulders, but it felt like the load lifters were pulling a bit on the top of the harness.
Now, to be fair, I was keying in on every little aspect of the fit and feel for this review, but it is something I noticed. It was not necessarily uncomfortable, and that “pressure” never increased, even during my four-mile packout with 120 pounds.
If anything I felt like that pressure somehow got better with the extra heavy load. I am not sure how, but the pack felt better the more weight I put in it, and never once did I have it slip on me, even during that long packout. I realized when I got back to the truck that I did not have to “hike up” the pack up during the packout. That is pretty incredible with a 120-pound load.
The Frame – Exo Mountain Gear K4 Pack Review
The frame of the Exo Mountain Gear K4 5000 is where a MASSIVE change came for the K4 packs. These frames are drastically different than previous Exo packs. As you can see in the above picture, the new Exo K4 frame is significantly narrower, and has a more pronounced taper than the K3. I was honestly fairly concerned about how narrow the bottom of the pack is as I foresaw issues with having enough surface area to strap large elk quarters to.
I had opportunities to test the Exo Mountain Gear K4 frame on several hunts packing out both deer and elk, and while I found that the pack is narrow, it did not seem to affect the performance or ability to strap on more than I was physically able to carry.
That being said, I found that because it was so narrow, it was a little more difficult to strap on those large loads, particularly if you are using the Nalgene water bottle holder. As you can see in the above photo, some of the quarters of this whole mule deer buck that I was strapping on crushed the Nalgene holder because the quarters were simply wider than the frame of the pack.
I also found that because of the narrow frame of the redesigned Exo Mountain Gear packs, the meat of a larger animal like this quarter of a bull elk we took bulges out more than other packs I have tested. However, once I got it strapped on, the load-hauling performance was better than any pack I have ever tested, so I was happy to put up with a little extra effort to get the load strapped on. A little more surface area to work with would be nice though.
Bag Configuration – Exo Mountain Gear K4 Pack Review
The bag of the Exo Mountain Gear K4 pack also got an overhaul, adding some nice large zippered side pockets for your spotting scope and tripod or other gear like a tent. I found these to be exceptionally well thought-out as they are pleated to give you a TON of volume if needed, and I was able to fit the Kowa TSN 99 and the Zeiss Victory Harpia 95mm spotting scopes in them with ease, even with a full pack.
The zippered side pockets’ ability to allow even large spotting scopes to be put in and taken out when the pack is full is probably one of the most impressive things about the design of this bag. No need to decompress the pack to make room for it. Just unzip and insert the spotter.
Of course, something like the Maven S.2 Compact Spotting Scope fits with ease, along with the above-shown Aziak Backcountry Lite Tripod.
Now, I did find that tripods which do not collapse down to less than 21 inches like the Really Right Stuff Ascend Tripod that I used this year do not fit quite as well, and I found myself putting the legs in the side stretchy pocket, securing the top of it with the top compression strap. Not a big deal, but keep in mind that those longer tripods do not fit quite as well.
The Lid – Exo K4 Review
The lid on the Exo Mountain Gear K4 pack was an area that did not change a ton, but there were a few key updates that were definite improvements from the K3 lid. One of the things that I did not care for on the K3 lid was how, if the bag was not full, the lid would work its way down to the middle of the pack unless you were diligent about tightening the lid straps. That certainly changed with the K4.
An entirely new design with how the lid attaches to the frame ensures that the lid straps will not slide off to the side, which is what allowed the lid to work its way down the pack with the K3. The updated K4 threads the straps through a steel guide which keeps the lid alignment just right. Now, I did find that these straps eventually worked their way loose over the course of a day of hunting, so I still found myself tightening them throughout the day to keep the lid from sagging, but it was NOWHERE NEAR as much as the K3.
Detaching Bag – Load Hauling – Exo Mountain Gear K4 Pack Review
On the Exo Mountain Gear K4 packs, detaching the bag to access “meat-hauling mode” is straight-forward but not as simple as the K3. One of the things I love about the K3 was just how easy it is to break the pack down and get it into load-hauling mode. However, that simplicity was a part of what led to the issue noted above with the lid tending to slide down and sag.
This re-design of the Exo K4 eliminated that issue of the lid sagging, but the process of converting the pack to meat-hauling mode takes a little more dexterity. While it is something I am more than willing to accept, when it is cold out and finger dexterity is suffering, this task can be a bit tougher to accomplish. Additionally, the process has an extra step or two, so it is something you want to practice a bit and make sure you know how to do it right before it is time to throw 100+ pounds on your pack.
Accessories – Exo Mtn Gear K4 Pack Review
HIP BELT POUCH
A hip belt pouch is a hip belt pouch, but with the new laser cut Molle webbing on the Exo K4 hipbelt, the new hip belt pouch is much more secure and even easier to operate with one hand. It is a small thing but a great improvement.
NALGENE WATER BOTTLE HOLDER
Folks had been calling for a Nalgene water bottle holder from Exo Mountain Gear for a long time and they finally delivered! Not only did the make one, but they made it so it attaches to the K4 hip belt in a way that is easy to access, transfers the weight to the frame, and is out of the way toward the back of the hip belt. Simply put, it works and works WELL.
LOAD PANEL
The Exo Mountain Gear K4 Crib Load Panel is similar to the one on the K3, with one main difference that I noted: the lower attachment point was moved from about three-quarters of the way down to just above the bottom of the frame. I am not going to lie, I was immediately disappointed when I first saw this. Based on previous experience with other packs that feature a load shelf that sits lower on the frame, I was not one bit excited about this change.
That said, I wanted to give this new design a fair shake, and once I got over my initial disappointment, the proof of the design was in the pudding….or packing in this case. For purposes of hauling sand bags on training hikes, especially when using a smaller sand bag, I still prefer the Crib attachment point to be higher up on the frame. In those instances, or when your load is simply smaller, the lower attachment point makes the load ride a bit lower than I like.
An easy fix to this would be to add a second Crib attachment loop to let folks decide which works best for the load they are carrying that day. The lower attachment points work great with larger volume loads but not as well with smaller loads.
QUICK-RELEASE RIFLE CARRIER
The Exo Mountain Gear Quick-Release Rifle Carrier was added to the list of accessories available with the K4. While the K3 also had a rifle carrier, it did not have quick-release functionality, which for many is a deal-breaker. As with most rifle carrier systems, I am always a bit skeptical as they often do not work well or do not work while the pack is loaded with meat.
To my surprise and appreciation, the Exo K4 Quick-Release Rifle Carrier is not only easy to operate, it works extremely well with the pack empty or full, loaded with a full meat load or in day pack mode. No extra straps to get in the way like others I have used. I can honestly say it is by a wide margin my favorite rifle carrier of all that I have tried to date.
It is not perfect, though, as I found it nearly impossible to put the rifle on your pack while wearing it (as you can do with some others that I have tried). The only way to secure the rifle to the pack is to take the pack off. This can be annoying if you pull your rifle off while hiking but want to put the rifle back on. The other “problem” I found is that the butt of your gun can be tough to get in the butt stock support pocket which seems a bit undersized. This was especially tricky with my XLR Element 4.0 Chassis as I nearly always scraped or pinched my fingers putting the rifle in.
The other thing to consider is that the initial attachment/setup is not the most intuitive, so make sure you take the time to watch the videos and get it configured properly so you get the right fit for your rifle. Depending on your rifle dimensions, you may need to adjust the height up or down based on your in-field experience.
GARMIN MINI POUCH
Another new accessory from Exo Mountain Gear is the Garmin Mini Pouch that attaches to the shoulder harness. While it is simple, it is also very useful and keeps your Garmin Mini readily available if needed. I was not sure if I would find it all that beneficial, but after using all season, I hardly noticed it was there when not in use and I basically just left my Garmin Mini in there for the whole season except to charge it. It helped ensure I brought the device even when I did not anticipate needing it, but it is always a good safety measure to have it on hand.
What I Liked – Exo Mountain Gear K4 Pack Review
Since they started, Exo Mountain Gear has come a LONG way in their design, but one thing has stayed the same – they continue to push the limits of what can be done with a backcountry pack, and they flat knocked it out of the park with the Exo K4 pack. The list is long of what I loved about this pack:
- Best load-hauling ability I have personally ever tested
- Excellent bag design
- Incredibly lightweight for its load-hauling performance
- Durable and well-constructed
- USA made
- Well-placed pockets throughout bag
- Lid does not slide down pack like the K3 lid
- New lumbar pad is a MASSIVE improvement
- New hip belt is a HUGE improvement
- Quick-release rifle carrier accessory
- Nalgene water bottle holder
- Incredible customer service and warranty
What I Disliked – Exo Mountain Gear K4 Pack Review
One thing I have learned from the privilege of testing and reviewing gear on a near daily basis is that no piece of gear is perfect. By nature, compromises and decisions have to be made on what is most important and what aligns with your company and design mission. With that said, there are a few things that I felt had to be “put up with” in exchange for all the incredible improvements that we got with the K4:
- Narrow frame – meat tougher to secure and bulges out the sides
- Bag detachment more difficult
- Slight pressure on shoulders
- Lid straps still slipped a little
- Lower Crib Panel attachment point – no option for higher attachment
Conclusion – Exo Mountain Gear K4 Pack Review
Exo Mountain Gear certainly stuck with their vision in building some of the most rugged, comfortable, and simple, yet functional packs while somehow improving its load-hauling ability. The short list of things I did not like are things I am happy to put up with because you just cannot have everything. While not every change is something I loved (most notably the lower location of the Crib Load attachment point without an option to attach it higher up on the frame for smaller loads), most of the “cons” were associated with a more beneficial improvement that accompanied it.
Keep in mind that all of this just my personal opinion, and your preferences, needs, and wants may or may not be the same as what I desire in a pack. Take the information and feedback from this review and apply it to your use cases and make your own choice about whether the Exo Mountain Gear K4 pack will fit your needs.
At the end of the day, the Exo K4 pack is my favorite to date of all the packs I have tested, even considering the things I did not care for. Sure, there are a number of packs I have not yet tested, but until that time, the Exo K4 sits atop my list of packs.
One thing I can assure you is that these are extremely well-made packs, can likely carry more weight than you will ever want to (and do it comfortably), and are backed by some of the best customer service and warranty you will find anywhere. Give an Exo Mountain Gear K4 pack a try and I doubt you will regret it.
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