The Atom

Aimed squarely at the ultralight hiker, the Atom gives you easy access to everything you need to keep hiking all day long using the five pockets that are easily accessible when worn.

This pack has few load assisting features and, as such, is only intended to be used by those with dialled in gear lists who like to enjoy the freedom of a light pack and moving without a frame or hip belt.

Weight from 408g / 14.4oz (size M)

Load capacity 9kg / 20lbs max


Packing Space

Main Pack body
The main body of the pack is completely open, yours to fill as you wish. It is secured with a roll top closure that can be secured vertically for added compression or dry bag style.

Large front pocket
The front pocket can be sewn in either Dyneema Stretch material or Bullet Net, both offer capacious storage. The Dyneema Stretch is better for a cleaner aesthetic and off trail bushwacks (doesn't snag easily) and the Bullet net is better for packing wet gear and improved visibility of items but can snag when bushwacking. The bullet net option will increase the measurable volume of your bag by 5L.

Side pockets
Each pocket can hold 2.5L and are perfectly shaped to carry 2 x 1L smart water style bottles with ease. You can use the elastic drawcord to secure these items whilst walking and, should the elastic ever break or wear out, we have designed it to be easily replaceable.

Load Carrying

S-shaped shoulder straps
Sewn using 10mm foam, durable 210d Robic Extreema face fabric and breathable, soft 3mm spacer mesh.

Sternum strap
Elasticated and height adjustable.

That's it. This pack is for serious UL users only.


Shoulder pockets:
Super stretchy and big enough to hold even the biggest smartphones, a day’s worth of snacks or a 700ml water bottle. We offer these in sewn in or removable options. 

Our preferred choice is for sewn in as standard

Front zig-zag elastic
Removable and designed to be able to store a folded Z-rest or assist with air drying your clothes.

Side Compression options:

  • Elastic: These are there to secure a trekking pole or tent poles when stored in the side pocket, also a handy place to dry socks
  • Webbing: If you are carrying anything heavy in the side pocket, these are a slightly stronger option than elastic and have much greater compression strength

Ice Axe loop
Sewn-in loop to easily connect an ice axe or walking poles.



  • Weight* 408g / 14.4oz
  • Load capacity 9kg / 20lbs max
  • Height fully unrolled 68cm / 27"
  • Circumference at base 76cm / 30"
  • Circumference at top 84cm / 33"
  • Main body volume 25L
  • Side pockets volume 2 x 2.5L

* Based on Medium Torso Size before additional customisations


  • Weight* 420g / 14.8oz
  • Load capacity 9kg / 20lbs max
  • Height fully unrolled 68cm / 27"
  • Circumference at base 79cm / 31"
  • Circumference at top 86cm / 34"
  • Main body volume 30L
  • Side pockets volume 2 x 2.5L

* Based on Medium Torso Size before additional customisations


  • Weight* 438g / 15.41oz
  • Load capacity 9kg / 20lbs max
  • Height fully unrolled 77.5cm / 30.5"
  • Circumference at base 79cm / 31"
  • Circumference at top 86cm / 34"
  • Main body volume 35L
  • Side pockets volume 2 x 2.5L

* Based on Medium Torso Size before additional customisations

The Atom

A quick video run-through of The Atom

The Atom

Made for Movement

Aimed squarely at the ultralight hiker, The Atom gives you easy access to everything you need to keep hiking all day long.

Built with

EcoPak EPX200

Durable and lightweight, EPX200 is a recycled 200 denier face fabric with eco DWR finish, blue 45 degree cross ply and white recycled 70 denier backing fabric. 

The EPX200 is our choice for The Atom+ due to its eco credentials, waterproof qualities, light weight and added durability.

Not too shabby on the eye either.

Good to know

Can it fit a Bear Can?

Most bear cans will not fit inside our EP30 packs, but you can rig it on top using the top strap.

For larger packs (EP40 and above) a BV450 will fit with the base to your back or a BV500 will fit vertically with a little room at the side for a stuffsack.  

How long will it take to make?

Making great things takes time! Our lead time lets you know our estimated production time frame, this will change depending on demand, time of year and staff availability.

The up-to-date lead time can be found at the top of every page on our website and is relevant for all unfulfilled custom orders on our books.

How much does shipping cost?

Shipping rates are calculated at checkout based on your delivery information.


£3.95 Small Parcel (every small parcel ships on a 2 week lead time)
£7.95 for orders over £140 


£10 5-10 Days
£25 for orders over £120


£10 5-10 Days
£25 for orders over £120

The rest of the world

£15 10+ Days
£35 for orders over £120

If you live in a remote location, we may occasionally need to charge a small extra surplus for shipping. This will be calculated when we ship the pack.

Customers outside the UK will not be charged the 20% VAT included in almost all of our prices, but you may be subject to local tax and import duties.

Full details on our shipping page.

Can I check out in a different currency?

Yes! Scroll right down to the bottom of the website and on the left you can select your home currency - this will automatically show you the correct VAT free price for overseas delivery.

How to Choose

The Atom vs The Atom+


Customer Reviews

Based on 26 reviews
Possibly the best ultralight weight pack in the world!

I did extensive research into ultralight packs from all over the world before finding Atom Packs in my own backyard.
I didn't have time to wait for a custom pack so I ordered a limited edition Atom which looked pretty much how I would have customised anyway. It had a wait time of four weeks but arrived in two.
I was immediately impressed by the quality of the build and attention to detail but waited to write this review until I had done a two week through hike with it. Home now and it performed to perfection and still looks brand new. I bought the optional padded belt as I knew I would be carrying pretty much to capacity every day and it was sooo comfortable.
I love all the details on this pack; the asymetric back pocket, the strap pockets which are just the right size for a phone or snack, the bottom pocket which is just right for a map or guide book and the fact that the chest strap is adjustable so you can get it just right.
Overall an amazing pack for a very resonable price.

Genuenly the best pack ever made

Its been 1 year and 1000 miles with the Atom 35 (GDT + smaller trails). This is the best pack I've ever owned. Its beautiful and so well made/stitched. Quality is state of the art, as good as you could wish for. It always has a place on the wall when I'm not hiking to be looked at. I customized mine pretty extensively and I love every additional pocket/zipper that was added. There is nothing about it I would change.This year it's gonna make people on the PCT jealous.

Marty Elliott
Ultralight perfection

Have about 500 miles on my Atom. Wearing this pack with a base weight under 10 lbs, it practically disappears on your back. Recently, I needed to load up with four additional liters of water, which pushes the packs weight limit. I could finally feel the pack, but it was not uncomfortable. I also have a Palante Simple and this pack blows it away for comfort, quality and ease of use. All of the pockets are deeper and carry items without sticking 1/2 way out. Build/shipping was very reasonable for cottage company. If you are ultra light, there is no better pack on the market.

John Skinner

I bought a standard Atom 40 a couple of years ago and since then it has been on countless adventures with me. It's a superb pack for an overnight adventure with my lightweight kit as it allows me to carry luxury items or extra clothes in a cold snap . As a daypack it performs really well also however I would recommend cutting an old rollmat to the size of the back panel for day hikes as frameless packs can be uncomfortable when carrying light loads of lumpy gear.

On my recent hike of the GR10 it performed incredibly well. The bottom pocket stretched beyond what I thought possible to accommodate the enormous amount of snacks you need when hiking all day and the stretch front pocket held my tent outer, groundsheet and pegs and other stuff with room to spare. The side pockets held my water bottles and fuel bottle secure the entire time, even when scrambling they did not budge.

I had to do a couple of 6 day food carries in the course of my month long trip. Even with my bag bursting at the seams thanks to the stupendous quantity of food I needed and carrying more than 2 litres of water bringing the weight of my bag well above what Atom Packs recommends as the maximum, the wide and well shaped shoulder straps helped to distribute the load surprisingly well.

The waterproofing has also held up over the course of time. The fabric is very durable for the weight, it was scratched by rocks and low hanging branches almost every day and the pack still looks like new.

The last pack you'll ever need

I've had my Mo60litre custom for about a year and a half and have done 600 miles+ mostly on the CWT northbound and then southbound. I've usually carried around 12kg and not noticed I had a pack on after a day or two of walking. More amazingly the pack still looks like new and has no signs of wear or abrasion. The roll top gives you versatility in the amount of stuff you need to carry and the outside pockets allow for loads of overflow and add ons. Comfortable, beautifully made, light and practicle. Very happy.