ZPacksô Arc Blast Backpack
Our Patent Pending Flexed Arc carbon fiber frame creates an air gap
against your back for a super comfortable fit. The air space keeps your back cool and also
provides a buffer from any lumpy items in your pack. The curve of
the frame is adjustable for optimal air flow and fit. No extra
The pack is constructed from tough 2.92 oz/sqyd Cuben Hybrid fabric.
This material is Cuben Fiber on the inside with a
protective layer of 50 denier Polyester on the outside. The outer layer
gives it even more strength, prevents fraying, and gives it a nice solid
color. The material and design can handle loads up to 30 lbs (14 kg).
There are three pack volumes to choose from. The torso height
and belt size choices are independent of the pack volume.
45L Pack Size:
Total Volume: 45 Liters / 2,750 cubic inches - 16.8 ounces
Main Body Volume: About 32 Liters / 2,000 cubic inches
Body dimensions: 5.5" x 12.5" x 30" (14 cm x 31.8 cm x 76 cm)
52L Pack Size (the original default size):
Total Volume: 52 Liters / 3,200 cubic inches - 17.0 ounces
Main Body Volume: About 39 Liters / 2,400 cubic inches
6.5" x 12.5" x 30" (16.5 cm x 31.8 cm x 76 cm)
60L Pack Size:
Total Volume: 60 Liters / 3,650 cubic inches - 17.2 ounces
Main Body Volume: About 47 Liters / 2,850 cubic inches
7.5" x 12.5" x 30" (19 cm x 31.8 cm x 76 cm)
The side pockets account for 5 Liters / 300 cubic inches and the
mesh center pocket is 8 Liters / 500 cubic inches, and are included
in the total volume.
Standard Features on the Arc Blast backpack:
- Our ultralight Flexed Arc carbon fiber frame keeps the pack stiff
so that most weight is carried on the hips instead of the
shoulders. The frame pieces and mesh back panel can be easily removed or replaced.
The frame is curved to allow air flow and keep your back cushioned
from the pack's contents. You can adjust the curve by tensioning
the mesh back panel. The recommended arch is about 2.5" (6 cm).
- Roll top closure (like our
dry bags) keeps water
out, and lets you roll down the top as your gear load shrinks. All seams and attachment
points are taped, making the pack highly water resistant.
We still suggest using dry bags for your important items like your
- Comfy 3/8" thick by 2.5" wide padded contoured shoulder straps and padded
Both the straps and the belt have a daisy chain for clipping on
items, and an adjustable position sternum strap is also
- Side pockets are sized to fit 1 or 1.5 liter bottles. They are
positioned low on the pack and slanted forward for easy access
without removing the pack. The pockets have drainage holes at the
bottom, and elastic that keeps them tight at the top.
- Large stretchy mesh center pocket is great for quick access items. Mesh
also lets you dry wet clothing and gives you a clear view of your
- Side compression straps are made from non-stretch Dyneema cord
for squishing down the pack volume. They also allow you to stand tall
items like trekking poles in the side pockets.
- A top strap, and base straps allow you to lash on extra items
to the top or base of the pack. The straps come off if you don't
- A centrally located Hydration Port is included to string out a
drinking tube over either the left or right shoulder. It is just
above/between the shoulder straps and it has a triangular cover to
keep out water. A water bladder can either be
hung from an internal hang loop, or laid horizontally on top of
- The default pack size has roughly 52 Liters / 3,200 cubic
inches of volume which is enough for
extended trips. The pack can be compressed down with the roll top
and side straps for short trips, or use the top strap and base
straps to lash extra stuff to to the outside for long carries.
- All standard Bear Canisters, including the Bearikade
Expedition and the BearVault 500 will fit in the upper half of
this pack standing on end. There is enough extra girth to either
wrap a foam pad around the canister (if you use one), or stand a
medium stuff sack vertically beside the bear canister.
- The frame on this pack is short enough to be used as a carryon
when flying. It will easily fit into standard overhead bins. Note
that the vertical frame bars are simple to pop out and can be
carried diagonally if you run into trouble. If you choose a torso
height of 23" or up the frame is lengthened to 25.25" and may not
fit in overhead bins unless it is removed.
- All ZPacks gear has a one year warranty against defects in materials or
workmanship. Returns or exchanges are welcome.
- For more info check out the
Backpack FAQs. Make sure to hop down to the bottom of the page
for Reviews and Testimonials.
The torso height on our backpacks is the actual distance
on the backpack
measured from the bottom of the belt to where the shoulder straps attach. Your
best bet for sizing is to find an existing pack that you like and measure it
directly. Note that the curve of the Arc frame affects the position of the
shoulder straps, and the curve is factored into our measurements. The shoulder
straps should be positioned level with, or a bit below the tops of your
By default this backpack comes without Load Lifter straps, and they aren't
really necessary for ultralight loads. If you do add Load Lifters it is ok to
have the shoulder straps a little lower, because the load lifters pull the
straps up off your shoulders.
If you aren't sure about the torso height, or if you want more flexibility there
is also an option below to add an adjustable torso range.
The belt size is the length of the belt padding from tip to tip. For example, a medium 30 inch (76 cm)
belt has 30 inches of padding from tip
to tip. The belt can cinch down to the point of the padding just about touching
in front. The belt webbing extends at least 10 inches (25 cm) or more beyond the
Use a string or cloth tape measure pulled tight around the spot on your body
that you want the belt to ride. You want at least a few inches of webbing in
front to allow for adjusting the buckle. If you are on the line, size down so
that you have room for adjustment. As an example, if you measure 35 inches, a
medium 30 inch belt would give you 5 inches of webbing to adjust in front but a
large 34 inch belt would barely fit with almost no room for adjustment.
Note that the "Indigo" color looks blue in the photos but it is actually a deep blue-purple.
Indigo and Orange backpacks have a Gray panel against your back as shown. All the other color choices are a solid pack color.
All packs have black pockets.
Backpacks are made to order. There is currently a lead time of about 6 weeks
. We are unable to take
additional due dates less than 6 weeks out until our backlog decreases.
Please note that if you choose a torso height of 23" or up, the backpack frame
is lengthened from 22.75" (58 cm) to 25.25" (64 cm).
Adjustable Torso Height and Load Lifter Straps
This feature is borrowed from our Arc Haul backpack. It allows you to move
the shoulder straps up or down within a range to dial in a perfect fit. It
works like a conveyor belt. This is useful for young hikers who are still
growing, or if the pack may be shared among people with varying heights, or
for resale value down the road.
This option Includes Load Lifter straps, so don't add them separately below.
Load lifters help lift the straps up off your shoulders, and they pull the
top of the pack in closer to your back. You can position the shoulder straps
just below the top of your shoulders.
This option overrides whatever torso height you selected above.
Please note that if you choose the Tall torso height range, the backpack frame is
lengthened from 22.75" (58 cm) to 25.25" (64 cm). If you are on the line and do
not want the taller frame sticking up behind your shoulders, get the Medium
Weight: 1.0 oz / 28 grams each
Load Lifter Straps
If you prefer to keep your shoulder straps attached to the backpack at a
fixed position, you can add Load Lifter straps by themselves. They connect
the shoulder straps to the top of the frame. These can be helpful to pull
the shoulder straps up, and pull the top of the pack in towards your
shoulders. These aren't strictly needed for ultralight
Weight: .2 oz / 5.7 grams Price: $8
These clip to your shoulder straps and are an excellent spot for your
camera, GPS, phone, sunglasses, or other items that you want to grab quickly. Mesh
on the front of the pouch gives you additional storage for small items like chap
stick, keys, etc. They can also be used for .5L water bottles to
counter balance a small pack.
These are detachable and can be used on non-ZPacks backpacks as well.
They are symmetrical and can be switched left or right.
Weight: .5 oz / 14 grams each
Price: $21.95 each / $41.95 pair
Shoulder Pouch Details
These pouches clip securely to the daisy chain on your padded belt.
They have taped seams, a waterproof zipper, and are highly water
resistant. Each pouch has about 1 liter of volume and is perfect for
maps, snacks, hat and gloves, gadgets, you name it.
These are detachable and can be used on non-ZPacks backpacks as well.
They are symmetrical and can be switched left or right.
Dimensions: About 6" wide, by 2" deep, by 5" tall.
Weight: .75 oz / 21 grams each Price: $21.95 each / $41.95 per pair
Belt Pouch Details Here
Multi-Pack - Four in One Backpack Lid / Chest Pack / Belt Pack
This four-in-one backpack accessory can be attached to the top of
your pack as a lid, carried on your chest as a front pack, or worn
at your hips as a fanny pack, or carried over your shoulder as a
satchel. About 3.5 liters / 215 cubic
inches volume. This will also work on non-ZPacks backpacks as long as
there are loops to clip it to.
Weight: 2.9 ounces - 82 grams Price: $39.95
Multi-Pack Details Here
Top Side Pockets
These pockets have a loop at each corner to connect them to
corresponding loops on the sides of your pack. Since these are not sewn to the pack
you can still stand tall items like trekking poles, an umbrella, or a
fishing pole behind the pockets. The pockets can be taken off or added
The dimensions are roughly 6" wide x 3" deep x 8" tall.
They are a good fit for:
-A 1 Liter or smaller pot
-A 1 Liter water bottle
-A water filter
-A poncho or light jacket
-Hat and gloves
-An inflatable sleeping pad.
Weight: .5 oz / 14 grams each Price: $18 each / $35 per pair
A small pocket with a zipper is sewn inside the backpack just above the shoulder
straps. This is a good spot to safely store your car keys and wallet
until you get back to the trailhead. The pocket is located near the
top of the pack so that you can access it w/o digging too far into your gear.
The pocket measures about 7" wide x 5.5" tall (18 x 14 cm).
Weight: .2 oz / 6 grams Price: $10
Ice Axe Loops
A pair of loops are attached at each corner of the pack for securing ice axes, one at each corner. The head of each axe secures through
a loop at the bottom, the handle is kept tight at the top with a shock cord band. The loops can all come off when
you aren't carrying axes.
Weight: .1 oz / 3 grams Price: $3
Trekking Pole Holders
One adjustable shock cord loop is attached to your shoulder strap and another
loop is attached to your belt to temporarily hold a trekking pole.
These are convenient if you want to quickly stow your poles for
climbing, or road walking, or other situations where you don't need
your poles temporarily. You can stow them and retrieve them without
stopping to remove your pack. You can carry both poles on the same
side if you prefer.
You can easily attach these to any older ZPacks backpacks, or other
brand packs. They can be moved to either side, or you can get them on
Weight: .2 oz / 6 grams per side Price: $3 per side
Shock Cord Lashing
3/32" Shock cord is criss-crossed along the front of the backpack. It can be
used to compress the pack, or to strap on items. The shock cord can be
detached when not needed. It does get in the way of the center pocket a bit.
Weight: .5 oz / 14 grams Price: $6
A lumbar pad cushions your lower back and increases the air gap behind
your back slightly. If your belt is just a little too large, this reduces the belt circumference by about an inch.
Typically you might carry something soft at the bottom of your pack like
your sleeping bag, so you may not need any extra padding at the lumbar area.
This pad slides on or off your existing belt and is held in place by
two bands on the back. It is also tied in place at the bottom center so that
it can't ride up or down. This may not fit on non-ZPacks backpacks.
Weight: .6 oz / 17 grams Price:
Roll Top Dry Bags
Up to 6 size medium or medium-plus size roll top bags will fit inside the body of the
pack, and up to 3 more can be strapped on to the top and bottom of the
pack for long carries. That's alot of capacity! Put your heaviest
items (food, water) on the inside of the pack close to your center of
gravity, and lightweight items (tent, clothes, pad) on the outside if you
run out of internal space. The Large Rectangle Food Bag is a good fit for this pack.
Roll Top Dry Bags
A medium Cuben Fiber Pack
Cover, or a Pack Liner
are also sized for this pack.
If you have emailed us about adding special features to your pack you
can add custom charges to your order from the
The Arc Blast backpack was originally designed in 2012. Prior to that most of our
backpacks were "frameless" and relied
on a folded or coiled sleeping pad for support. I did my first three thru-hikes
(AT, PCT, CDT) with frameless packs very similar to our current Zero backpack.
Frameless backpacks are ok for super ultralight loads, but they start to get
uncomfortable on the shoulders when they are pushed beyond about 20 lbs (9 kg).
On a long hike, heavier food and water loads are inevitable.
Our goal was to create a comfortable pack with a frame without adding any more
weight than necessary. A frame keeps the pack rigid making it easier to pack and
it also holds its shape when half full. A frame transfers weight to the belt, and feels alot better on your back and shoulders when pushing weight loads into the 20-30
My wife Sheryl and I gave Arc Blast backpacks their first big test on our
2012-2013 Te Araroa thru-hike in New Zealand. This hike was close to 1,900 miles
and four months long across all types of terrain the length of New Zealand (Trip
report / Gear list
Our packs held up very well on that trip with minor wear and tear. Since then we
have added taped seams and more strategically placed reinforcements for even
better longevity. Our packs felt great
. They were a big improvement in
comfort over the frameless packs we had used in the past. The extra few ounces
for the carbon frame was totally worth it, and the cushion and air flow against
our backs was appreciated in the warm, wet, humid New Zealand weather.
Our longest carry on that trip was through the Richmond Range. We
carried a starting weight of about 35 lbs (16 kg) with 9 days of food. The Arc
Blast feels "heavy" at that weight, but not terribly uncomfortable. It is ok
once in a while. The recommended comfort limit is about 30 lbs (14 kg). If you
need to carry higher loads regularly, consider the
Reviews and Customer Testimonials:
Please email us with feedback (good or bad) if you have any!
Adventure Writer Keith "Fozzie" Foskett
reports from his 2013 El Camino
de Santiago thru-hike with his Arc Blast!
Read his informative Arc Blast review with photos
Update- Keith has finished his second El Camino de Santiago hike in 2014. "My
now has 1900 Miles on the clock and it barely seems worn in."
"On the impressiveness scale, I would put the load carrying abilities of the
ZPacks Arc Blast, for loads in the sub 20 range, at exceptional."
Check out the full
by John Abela (Hikelighter.com)
"The Tour Du Mont Blanc was amazing! The Arc Blast did exceptionally well carrying
all of my gear and food for 8 days of travel through the French, Italian, and
Swiss Alps!" -Ben Smith (Goosefeetgear.com)
"I just wanted to let you know that I received the pack today. I had extremely
high and unfair expectations from the reviews and recommendations I had
received, which the Arc Blast has (somehow) more than surpassed! This is my
first ZPacks product and I am just blown away by the craftsmanship and
I was expecting some imperfections from a smaller company, but the stitching
and the water taped seams are just beautifully done, as is the rest of the
pack. On top of all that, I just loaded it up with a lot extra gear and the
weight transfer is unbelievable, couldn't really tell the difference between 1
pound and 15 pounds." -Rocky J.
"Got back from my Sequoia adventure with the Arc Blast pack. I was a little
apprehensive, I didnít think a one pound pack would handle 35 pounds, expedition
canister with food for 9 days included. We weighed them with scales before
heading off to trail. At that point I was committed and thought ďoh boyĒÖ.
I must say this was the most comfortable pack Iíve ever used. And Iíve used ULA,
Six moons, and granite gear stuff. Pleasant surprise!" -Chuck T.
"Thanks for the Arc Blast. We loved it. Best, and lightest of the breed. We used
it for four days and three nights through about 32 miles and 6000ft of up and
down , rain, sleet, hail, and snow without any fault or discomfort. Also,
survived six airplane rides and several mad dashes through the airport with a
full load. I'm sure this is nothing compared to what others have done with the
pack." -Arlo A.
"I have been using the 60 liter Arc Blast backpack I purchased from you for a
couple months now. I love the pack and I think it's the most perfect designed
and constructed pack to be found anywhere. I have shown the pack to lots of
hikers and recommended it to everyone." -Chuck F.
"Your products have changed my life. I went on the most comfortable backpacking
trip of my life last weekend using the Arc Blast, sleeping bag, hood,
toothbrush, towels, just about everything you sell, haha. Thanks so much for the
wonderful products and your amazing customer service, I will be singing your
praises up and down the PCT this summer." -Otto R.
"Alyson & I canít thank you enough for how much we enjoyed the zPacks gear
during our recent walk in Spain. Itís not just the light weight Ė the Arc Blast
packs are so well designed we just put our gear in and everything was so easy to
access when we needed it." -Mark & Alyson
"The backpack was comfortable and survived the harsh environment on the
Larapinta Trail in Australia. One of the most comfortable packs I have used.
Just large enough for 10 days gear and dehydrated food, three litres of water
and SLR camera. Start weight about 17kg."
"Just completed the GR-5 last week in France. The
pack was fantastic,
easily carrying 10 kgs, completely water resistant through every thunder storm,
and unbelievably light. Thanks for a great piece of gear." -Avi. (photo
"I seem to have (inadvertently) got the JMT southbound record time 4 days, 8
hours, 43 minutes. I used a lot of ZPacks kit on this trip - Arc Blast pack,
Hexamid tarp, ZPacks sleeping bag, WPB rain jacket and kilt." -Ralph Burgess
I am not a super-light hiker but an older guy incrementally dropping
weight. I was surprised how comfortable the Arc Blast was. I expected to "give
something up" in order to drop weight. Not the case with the Arc Blast! -Doug L.
"The pack is great! 6 days in the Grand Canyon loaded with water, 8 days
bushwhacking in the Wind Rivers, 6 days on the AT, all loaded for the duration.
Carries far more weight than you rate it for and does so well ... it's a
beautiful thing and my favorite of all my packs!" -Bob M.
"The Arc Blast I got some time ago worked great at Philmont this summer, even
when hauling up to 50lbs. The Scouts still haven't learned anything about light
weight food, so we had plenty of canned goods and gallons of water due to the
drought. The pack was uber comfortable, even under such heavy loads. Love your
gear!" -Daniel L.
Disclaimer: You probably should not carry 50lbs in this pack, but it is nice to
know that you could in extreme circumstances. 30-35lbs is a more reasonable
"I just returned from a 10-day trip in the Sawtooth Wilderness in Idaho. The Arc
Blast pack was wonderful. It is the best backpack that I have ever owned. Thank
you for lightening my load by approximately 2 pounds from last year's trip!"
"I used the Arc Blast on my recent JMT thru hike. The pack performed perfectly!
It was super comfortable even with 7 days food in my 12" Bearikade (about 31 lbs
total weight) and shows no visible wear and tear. I actually saw several other
hikers with the same pack and 100% of the people who had them loved them! I put
the Bear can in the middle of the pack to avoid any potential wear and
tear on the bottom, and the weight distribution was great." -Mick P.
"Thank you for quickly sending out my new backpack to Reds Meadows. My old pack
was falling apart and I was able to complete the John Muir Trail without
interruption. The Arc Blast fits perfectly and was a joy to carry. Many people
asked about it and we gave them your website! The Hexamid solo is still working
wonderfully after 3700 miles too! Hope you continue to have great success with
your business." -Jellybean
"I just finished a JMT thru-hike with a 60L Arc Blast and a Hexamid Duplex, and
they both worked fantastically. The pack held my BearVault 500 with a peak
weight of about 25 lbs without problem, and it still looks in good shape!"
"This year I was trekking in the French Alps and found Arc Blast just fantastic!
It sits very well on your body, I could easily adjust the frame to regulate the
distance between the pack and my back, size and placement of the side pockets is
very good, my drink bottles and small snacks were very safe there. I felt like
backpack was very well 'united' with my body. We were trekking through some
difficult terrain and it was very comfortable, I'm really impressed. I did get
some tiny scuffs on the bottom from resting it on sharp rocks, but other than
that it is great. I'm so glad my friend told me of your website." -Ewa K.
"Just wanted to send a quick thanks for my Arc Blast! I have been absolutely
loving it and giving it a workout. Best pack I have ever owned. Here's a view of
the Chinese Wall
in The Bob Marshall Wilderness." -Will F.
"I received my 52L Arc Blast a couple of weeks ago and am more than
impressed with the quality, workmanship, and the overall comfort! Iíve never
hiked 20 mile days in a more comfortable pack! I donít even feel like taking it
off during breaks on the trail! Its INSANE!!! I tell all my hiking partners and
friends about you guys!" -Rock S.
Fellbound discusses the merits of his Arc Blast Backpack and his Challenger Rain Jacket
in this Arc Blast Review
"My pack rocks. I really like the lumbar pad Ė just that extra bit of comfort and also stands it off my back a tiny bit more.
Plenty of ventilation, but still firmly in place. Carries loads from 15 to 25 lbs with ease.
Very, very nice; and gets lots of comments on the trail." -David A.
"Thanks a lot Joe. I just took the Arc Blast out on a 5 day section hike from Deep Gap NC to Fontana Dam.
It was awesome! I had a fairly low pack weight but it felt like I was not using a pack at all.
I also tried out my new Duplex tent, 30F Down bag, and Challenger rain jacket. They all performed really well.
I had a lot of interest from AT thru hikers I met on the trail.
I took the opportunity to sing the praises of your great equipment." -Michael H.