Zpacks Arc BACKPACK Review

JUMP TO: OVERVIEW OF ARC RANGE / QUICK SPECS / MATERIALS / ACCESS & FRONT POCKETS / VOLUME / WEIGHT / DURABILITY / FRAME & BACK PANEL / HIP BELT / SHOULDER STRAPS / WATERPROOFING / ADD-ONS / SUMMARY

Author: Sam Brilleman

The Zpacks Arc range of backpacks are without a doubt amongst the best ultralight backpacks for multi-day backpacking.

They are uber-light, extremely customisable, and comfortable… as long as you keep your base weight well within the recommended range.

In this article I discuss the differences across the Zpacks Arc range, as well as providing a detailed review of the features common to all backpacks in the Arc family.

OVERVIEW OF THE ZPACKS ARC RANGE

For most multi-day backpacking adventures you want to be considering backpacks from the Zpacks Arc range.

These are Zpacks larger packs which can comfortably carry up to around 30 lbs (14 kg) of gear making them suitable for most multi-day trips or thru-hiking.

The Arc range consists of the Arc Blast, Arc Haul, Arc Zip, and Arc Haul Zip.

Confused yet?

I initially was.

But never fear, it’s not too crazy. Essentially these four backpacks are distinguished by three key features…

Various combinations of these features result in four backpacks:

• Arc Blast: DCF + roll-top access + mesh front pocket.

• Arc Zip: DCF + roll-top & zippered access + zippered front pocket.

• Arc Haul: Gridstop + roll-top access + mesh front pocket.

• Arc Haul Zip: Gridstop + roll-top & zippered access + zippered front pocket.

I’ll describe these features in a bit more detail below. But in short, my personal favourite is the Arc Haul Zip with it's more durable Gridstop fabric and the convenient front loading zipper. 

I find the Arc Haul Zip works best for me since I can load my tent as the last item when packing up — it goes easily into the front pocket with room to spare. I also enjoy the option to use either the top access, which is convenient for accessing items during the day, or the front access, which is convenient for unloading my entire kit when I get into camp. In fact, much of the review below is based on my experience with the Zpacks Arc Haul Zip.

Of course your mileage might vary depending on your personal preferences, the amount of gear you carry, and how you intend to organise and access your pack during the day.

QUICK SPECS

Zpacks Arc Blast

Zpacks Arc Haul

Zpacks Arc Zip

Zpacks Arc Haul Zip

MATERIALS

For backpack material you will need to choose between a Dyneema Composite Fabric (DCF) (also known as cuben fiber) or a heavier Gridstop fabric.

The earliest Zpacks backpacks were made from DCF, while Gridstop is a more recent addition to the Zpacks line. The Gridstop is more durable, resistant to abrasions, and can support heavier loads. The downside is that it is slightly heavier.

However the difference in weight between DCF and Gridstop is almost negligible. For instance, the Zpacks Arc Haul (made with Gridstop) weighs only 85 grams more than the Zpacks Arc Blast (made with DCF). But that weight penalty alone is somewhat deceiving because the designs aren’t quite identical… since the Gridstop material is able to hold its shape and support weight than the DCF material, the Arc Haul is actually designed to be one inch deeper in the main compartment. What this means is that — although the Gridstop backpack weighs 85 grams more, you actually get an extra 7 litres of volume with that weight penalty.

So unless you are aiming to trim every ounce of your base weight, I think the more durable Gridstop material is generally the way to go.

ACCESS & FRONT POCKETS

The original Zpacks design comes with top access only. This is achieved via a roll-top closure similar to what is found on dry sacks.

This traditional design is found on the Arc Haul (Gridstop) and Arc Blast (DCF) backpacks. These backpacks also have a large mesh pocket on the front of the pack.  

A more recent alternative is front zippered access, similar to what is seen on many travel backpacks. This zippered access is in addition to the roll-top access, not instead of it.

The zippered access design is found on the Arc Haul Zip (Gridstop) and Arc Zip (DCF) backpacks. These backpacks also have an enclosed zippered pocket on the front of the pack instead of the large mesh pocket.

The zippered front pocket found on the Arc Haul Zip and Arc Zip is made from the same material as the rest of the backpack and uses a water-resistant zipper. The volume of the zippered pocket is also slightly larger than the mesh pocket that would otherwise be found in its place. So in essence, you get slightly more volume and waterproofing, but you sacrifice the breathability of a mesh pocket (which some people find useful for drying wet clothes etc).

Whether you opt for the roll-top access + zippered access + zippered front pocket or the more traditional roll-top access + mesh front pocket really comes down to your personal preferences.

VOLUME

The quoted volume of the Arc backpacks ranges between 55 litres (for the Arc Blast) and 64 litres (for the Arc Haul Zip).

The main difference in volume across the different packs is due to additional one inch of depth found on the Gridstop packs (as explained in the Materials section above) — this adds an additional 7 litres. The zippered front pocket found on the Arc Zip and Arc Haul Zip is also quoted as being 2 litres larger than the mesh pocket found on the front of the Arc Blast and Arc Haul.

These quoted volumes include the two side pockets (2.5 litres each) and the front pocket (either 8 or 10 litres). The main compartment therefore has a quoted volume between 42 and 49 litres depending on which pack you choose.

One thing to be wary of is that the arc in the frame (described in later sections) is customisable — that is, you can add as much or as little arc in the frame as you see fit. The downside is that more arc will reduce the effective volume of the main compartment! This means that you may find the effective volume of the main compartment to be quite a bit less than the quoted volume, depending on how you choose to set up your frame and back panel.

The volume of the front pocket easily swallows my Zpacks Triplex tent plus several other items such as rain jacket, rain pants and snacks.

Each side pocket is large enough to easily fit a 1.5 litre Nalgene bottle. And the side pockets are thoughtfully angled slightly forwards so you can easily remove (and replace) a water bottle without having to take the backpack off. Personally I have had no trouble getting my water bottle it in and out of the side pocket while wearing the backpack.

Zpacks state that all their Arc backpacks will fit a bear canister in the upper half of the pack, standing upright. Living in Australia, and not North America, I haven’t tried so can’t vouch for that claim.

These backpacks are of course targeted at lightweight backpacking, meaning they are most suitable for hikers who have begun to trim their base weight down a bit — this might mean owning a less bulky tent or a higher fill power down sleeping bag. If you are using a lot of heavier, larger, traditional backpacking gear then you might want to look for a pack with some additional volume.

Having said that, if you are using modern lightweight backpacking gear then the volume of the Arc backpacks should easily be large enough for most multi-day backpacking trips.

If you are concerned about space, then consider going for the Zpacks Arc Haul Zip — the extra volume over the Arc Blast will make a bit of a difference.

WEIGHT

As with all Zpacks gear, the Arc range of backpacks are pushing at the bounds of ultralight. I would almost call these backpacks uber-light.

Stated weight on the medium Arc Blast is 20.6 oz (583 grams). The weight of my Arc Haul Zip is around 29.3 oz (830 grams) — but that includes the addition of two hip belt pockets, a shoulder pouch, and a lumbar pad.

I’m still a bit undecided about whether I like the additional lumbar pad or not, but the hip belt pockets and the shoulder pouch are worth their weight in gold.

Backpacks don’t get much more lightweight that this!

So what are the sacrifices? A backpack can’t be this lightweight without sacrifices, right?

Well, yeah, that is kinda true.

The most obvious compromises — albeit they are both pretty minor — are durability and comfort. These are the two things I discuss next.

DURABILITY

I took my Zpacks Arc Haul Zip on a month long trip backpacking and hiking in Pakistan.

Big mistake, it only just survived.

It wasn’t the material that struggled the most on the Pakistan trip. It was all the moving parts. The Arc frame is highly customisable, but this means that parts of the frame are on the outside of the pack, removable, flexible, and… well… just not designed for getting thrown on top of a minivan or the bottom of a crowded bus.

At the end of a bus trip I would find part of the frame had popped out and was about to fly off the minivan never to be found again.

But for hiking thousands of miles of trail along the Pacific Crest the Zpacks Arc Haul Zip should easily last the distance.

On most hiking trips you are the only one handling your bag and so you are able to take a bit more care.

Nonetheless, like any ultralight backpacking gear you should treat the Arc backpacks with a bit of care. For example, try not to lift the pack by loose parts such as the hip belt when the pack is full. Be sensible with it and you should get many years of use.

The Gridstop packs (Arc Haul, Arc Haul Zip) will have a longer lifespan than the DCF packs (Arc Blast, Arc Zip). The DCF material will eventually start to wear through and/or shred when the Gridstop wouldn’t have. So if durability is a concern then go with the Gridstop, it’s probably worth the minor weight penalty.

Of course neither the DCF or Gridstop material is bombproof. So if you spent a lot of your hiking life bushwhacking then maybe consider something more bombproof like the HMG Southwest 3400.

FRAME & BACK PANEL

All Zpacks Arc backpacks have the same frame and back panel design. This consists of an external carbon frame and a trampoline style, ventilated, back panel.

The frame is relatively minimalist, with just three horizontal stays (top, middle, bottom) and two vertical stays. The hip belt is attached to the bottom horizontal stay and the shoulder straps (and load lifter straps) are attached to the top horizontal stay.

The two vertical stays are made from a carbon material that is highly flexible. The top and bottom of each vertical stay is connected to the back panel (which itself is a mesh-like material, separate from the main backpack compartment).

By adjusting the attachment points at the top and bottom of the back panel you are able to bend — or create an “arc” in — the vertical stays along each side of the backpack frame. This results in the “trampoline style” back panel. The more arc you create in the frame, the more tension and suspension there is the back panel.

LIVING WITH AN ARC IN THE FRAME

The main upside of this design is that it creates airflow and ventilation between the backpack and your back.

Another upside is that the arc changes the way the load is distributed. More arc pivots the pack so that more weight is placed along the rear of your hips rather than onto your shoulders.

On first reading this sounds ideal, but when the pack has quite a bit of weight in it this pivoting action can place too much weight on the rear of your hips and not enough on the front of the hips.

Reducing the amount of arc can actually bring the center of gravity of the pack back in closer to your body and thereby distribute more of the weight onto the front of your hips.

Zpacks recommend about 2.5 inches (6 cm) of arc at the widest point, however it will really come down to your sizing, the contents of your pack, and your personal preference.

Play around with it to find the setting that works best for you.

Personally I prefer using very little arc.

The amount of arc also changes the vertical distance between the top and bottom horizontal stays. This means that the amount of arc actually changes the torso length. So it can take a bit of adjusting to dial in the perfect fit for you.

Note that you are also able to adjust the location of the shoulder straps (moving them up and down) meaning you can adjust the torso length that way as well.

For more info check out Zpacks’ video on adjusting the fit of your pack, as well as their video on choosing the correct sizing.

PROS AND CONS OF AN EXTERNAL FRAME

One thing to note is that because the frame is external and adjustable there are numerous attachment points and straps.

This was one of the reasons I found that the Arc Haul Zip was not suitable for travelling and hiking through Pakistan… The numerous attachment and adjustment points for the external frame were prone to getting caught, tugged, or popping out of place (since some parts are removable).

Having said that, the upside of an external frame is that it is much lighter. For example, the Osprey Exos also uses an “arc” frame with a mesh trampoline style back panel. Although the Osprey design is super comfortable, one downside is that the frame is internal — meaning it is slightly heavier and not adjustable in the torso length (although several sizes are available).

HIP BELT

The hip belt is identical for all backpacks in the Arc range.

They consist of a foam that is passable in terms of comfort, but by no means as luxury as the memory foam hip belt found on the Gossamer Gear Mariposa or the Aarn Natural Balance.

But as long as you keep your total pack weight reasonable (say below 15 kg) then the hip belt should easily be comfortable enough.

I’ve found the foam on the hip belt to be enough for me — my hip bones seem to be fine during a multi-day hike. But my partner has found that the hip belt isn’t padded enough for her. I don’t know whether this is male vs female hips thing, or whether we just have different requirements for comfort in this regard.

The front of the hip belt has a v-style strap that allows you to dial in the correct level of tension both above and below your hip bone.

As you would expect on an ultralight pack, the straps and clips are no larger than needed… and thankfully so.

The hip belt is secured to the main pack via the horizontal stay at the base of the pack’s frame. This means that the base of the pack sits directly against your lower back — a different design to something like the Osprey Exos 48 which has a trampoline-style back panel that suspends the base of the pack away from your body (i.e. it is just tensioned mesh that makes contact with your lower back).

The Osprey Exos 48 is arguably more comfortable against your lower back since the contact point is much softer, but it has the downside that the hip belt is not removable.

I have found that if I put too much gear in my Zpacks Arc Haul Zip (say more than 15 kg of total weight) then the rear of the hip belt can get a bit horizontally twisted under the weight of the pack, and I can feel the horizontal stay at the base of the frame pushing against my lower back and/or tailbone.

I don’t seem to encounter this problem if I keep the pack weight below about 15 kg. And for what it’s worth, I have also been adding an additional lumbar pad, but this doesn’t seem to make much difference since both the hip belt and lumbar pad twist in a similar way.

Having said all that, my Zpacks Arc Haul Zip is still the backpack I reach for on most multi-day trips — not the Osprey Exos 48 — so the comfort of the hip belt is obviously still adequate enough! In fact, adequate enough to make it the overall top pick in my round-up of the Best Lightweight Backpacks.

Zpacks hip belts are available in a range of sizes, so when purchasing your pack you will need to choose the hip belt size appropriate for you.

Fortunately the hip belts are also removable. So if you choose the wrong size you can always send it back and switch it for another. Or, god forbid, you hike too many miles (or not enough!) and eventually need to replace the hip belt with another size.

SHOULDER STRAPS

The Zpacks Arc backpacks use S-shaped shoulder straps. S-shaped shoulder straps are the best option for a unisex backpack as they provide more space around the pecs for both men and women.

The shoulder straps are attached to the top horizontal stay on the backpack frame, although they are not sewn on directly to the frame.

Instead, they are attached to an adjustable “mechanism” (as Zpacks calls it) that allows the shoulder straps to move up or down. This makes the torso length adjustable. It also allows the straps to contour to the back of your shoulders.

There is also load lifter straps that allow you to pull the top of the pack in closer to your body (or more specifically — closer to the top of the shoulder straps).

The foam padding and spacer mesh used for the shoulder straps does the job and is comfortable enough, but perhaps not as luxury as the memory foam shoulder straps found on something like the Osprey Exos or Gossamer Gear Mariposa.

If you want a bit of extra padding, then Zpacks sell shoulder strap pads as an add-on.

The front of the shoulder straps have daisy chains for securing additional gear if you need, or for adding on features like their shoulder pouch or water bottle sleeve.

WATERPROOFING

An awesome thing about DCF and Gridstop is that both materials are waterproof.

Even more awesome is that Zpacks goes to the trouble of taping all the seams on their backpacks.

Couple that with the fact that they use a roll-top closure (on all their Arc packs) and water-resistant zippers (on the Arc Zip and Arc Haul Zip).

The result?

A backpack that is near on waterproof.

I wouldn’t suggest submerging your pack in the river without additional protection for vital items such as your clothes and sleeping bag. There are always going to be weak points — the inclusion of a hydration point being the most obvious one! But for the most part your pack is going to be waterproof against rain showers and even the most serious downpours.

Nonetheless I always recommend securing vital items such as clothing and sleeping bags in waterproof dry sacks.

Alternatively you can use a large trash compactor bag as an internal pack liner (or a “real” pack liner if you’d prefer that).

ADD-ONS, ACCESSORIES & CUSTOMISATION

I thought I’d save the best till last.

Add-ons, accessories, and customisaton.

This is perhaps one of the strongest points of the Zpacks Arc backpacks (well, aside from the fact that they are seriously lightweight).

Zpacks sell a number of add-ons for their Arc backpacks. The most notable are the hip belt pouches and shoulder pouches.

But there are additional add-ons like a water bottle sleeve, mesh side pockets, or their multi-pack (which can be used as either a front pack, a brain, or a day satchel).

You can see the full collection of available add-ons here.

Each of these accessories is sold separately, which is not ideal since the costs are relatively steep and do add up. But the flexibility with which you can customise your set up is awesome!

I personally have opted for two hip belt pouches, one shoulder pouch, and a lumbar pad. This gives me all the space I need for snacks, camera, and other items I need to access during the day, and adds little weight.

The hip belt pouches are pretty large — I can fit my headlamp, toothbrush, toothpaste, first aid kit, bug spray, lighter, sunscreen, Steripen, compass, and more… and that is just in one of the hip belt pouches!

Each pouch has a two-way waterproof zipper and all seams are taped — so they are essentially waterproof against all but the most serious downpours.

The shoulder pouches aren’t quite as large as the hip belt pouches but still big enough to do the job — I tend to just keep my Garmin inReach Mini inside the shoulder pouch, and then there is a small mesh pocket on the outside of the shoulder pouch where I store my lip balm and pocket knife.

The hip belt and shoulder pouches are available in both the DCF and Gridstop materials so you can match it to the pack material you choose. Having said that, the pouches are usually only available in black and not the full range of colours that are available for the backpacks.

SUMMARY

The Zpacks Arc Blast, Arc Haul, Arc Zip and Arc Haul Zip are all seriously ultralight backpacks that don’t sacrifice anything in terms of functionality.

In terms of weight and functionality, I would say that the Arc range of packs are one of the best, if not the best. This is where they earn their worth.

In terms of comfort, there is probably more comfortable packs out there. The Gossamer Gear Mariposa is one that comes to mind. Similarly for durability. The HMG Southwest is more bombproof than the Zpacks Arc Blast, for example.

But having said that the Zpacks Arc backpacks aren’t far behind in terms of comfort or durability either.

Weighing up these four criteria — weight, functionality, durability, and comfort — I think the Zpacks Arc backpacks are currently pretty hard to beat.

If the total weight you will be carrying is somewhere below 30 lbs (14 kg) then a Zpacks Arc backpack is one of the best ultralight packs you will find.

On the other hand, if you are carrying loads heavier than around 33 lbs (15 kg) then you are probably better off looking for a backpack that has a sturdier frame and more padding.

But with modern gear and a bit of trip planning, most backpackers should be able to comfortably achieve a base weight of around 15-20 lbs (7-9 kg)… and of course due to it’s ultralight design a Zpacks Arc backpack can help you get there!

This makes a Zpacks Arc backpack the perfect choice for most hikers looking to trim their base weight.

DISCLOSURE

I paid full price for the Zpacks Arc Haul Zip that I used as the basis for this review.

MORE INFORMATION

If you enjoyed reading this review then you'll likely love reading some of our other gear review pages:

• Gear Reviews Overview Page

• Best Backpacks

• Best Backpacking Tents

• Best Hoodless Sleeping Bags

Happy hiking and take care out there in the wild!