The lead time for all backpack orders as of 29th June is 8 weeks.

The Mo - Custom.

The Mo

Lightweight design, no compromises. 

It took us 12,000 miles of hiking to design our perfect hiking pack: the Mo - a lightweight, fully featured load hauler, purpose built to support you on your next adventure.
We designed The Mo to suit the average thru hiker using modern, lightweight gear. We use lightweight, durable materials that are easily able to cope with heavier loads and heavier use. If you are heading out onto rough and overgrown trails like the CDT or Te Araroa, then the Mo is for you! With a load capacity of 19kg/42lbs and pack weights starting at just 850g/30oz, The Mo won't weigh you down.

Tell me about The Mo:
  • Large front pocket - made with dyneema stretch and sewn with front elastic rolled over to protect the stitching – can stretch to hold up to 5L (although this isn’t included in total volume)
  • Side pockets: Two forward-facing, deep and low side pockets. Each big enough to keep two 1L Smartwater bottles steady while being low enough to reach whilst the pack is worn. Made with 210d Robic. 2.5L each. Replaceable elastic.
  • S-shaped shoulder straps sewn using our own laminated 10mm foam, durable 210d Robic face fabric and breathable, soft 3mm spacer mesh.
  • Dual adjustable hipbelt – 4 adjusters tighten by pulling inwards allowing you to dial in the perfect  fit. Compatible with our removable hipbelt pockets.
  • Lumbar pad with 10mm EVA foam and 3mm thick spacer mesh.
  • Roll top closure with 15mm vertical side compression – the roll top can also be clipped together at the top (dry bag style) and the side compression clipped around the front of the bag to aid carrying snowshoes or maybe a huge packs of chips etc.
  • Z side elastics – great for securing trekking poles, tent poles or drying your socks.
  • Front zig zag elastic over the front pocket – useful for stowing items quickly, rigging up solar panels or drying your laundry etc.
  • Y-strap – Great for storing sleeping pads, tents, or bear cans. (we recommend you clip your tent or valuable items to the bag – eek!).
  • Sternum Strap: Elasticated and height adjustable. Removable - weighs 12g/0.42oz
  • Ice axe/Trekking pole loop: sewn in 15mm webbing loop to connect walking poles or an ice axe.
  • Bear can: A BV450 will fit with the base to your back, a BV500 will fit vertically with room at the side for a stuff sack.

40L: 800g/27oz (40L, VX21, size medium with no additional pockets)
50L: 850g/30oz (50L VX21, size medium with no additional pockets)
60L: 900g/31.7oz (60L, VX21, size medium with no additional pockets)

Volume break down:

Internal volume 35L, 45L and 55L respectively (measured with pack closed and rolled three times)

2 x 2.5L side pockets

Large dyneema stretch front pocket can stretch to hold 5L (although this isn’t included in total volume)


The Mo 40L:
Top circumference: 36"
Bottom circumference: 33"
Height: 29"

The Mo 50L:
Top circumference: 37"
Bottom circumference: 33"
Height: 33"

The Mo 60L:
Top circumference: 39"
Bottom circumference: 34"
Height: 36"

      Body: VX21 X-Pac fabric

      Side pockets, Shoulder straps and Hipbelt: 210d Robic, Black

      Front pocket: Dyneema Mesh

      Backpanel: 500D Textured Nylon (similar to cordura)

      Base : VX21 black


      • Plastic frame sheet, with removable alloy stay
      • 8mm closed cell foam foam
      • Frame is removable – choose to remove the alloy stay (30g), or the whole frame sheet (120g) leaving just the foam (30g), or remove everything!
      Recommended load capacity: 19kg/40lbs – this is a guide only and will vary from person to person depending on fitness and strength

          Watch The Mo overview video
          Torn between The Mo and The Atom+?
          Check out our video explaining the specs and features of both these backpacks.


          What volume to choose depends on your gear set up and the length of time you will be on trail, this is personal to each hiker and can vary with each trail – i.e desert travel may mean you need to carry 10L+ of water, snow travel may mean increased bulky insulation etc. Each volume model of Mo has an identical frame and harness so their load-carrying abilities are the same. If you are heading out for 5-7 nights or more, or need to carry some extra gear, then the 60L version is still under 1kg and has the capacity you need when the load gets large, when this volume is not in use the roll top simply rolls down to the size of a smaller volume 40L pack. If you eventually find yourself travelling with lower weights, or simply need less backpack, then the entire frame system can be easily removed and left at home. This will reduce the weight by around 150g/5oz. The load-carrying capacity of the backpack will be reduced by 5kg/10lbs.

          We can ship backpacks all over the world using UPS, DPD and Royal mail.

          UK - £7.95

          US - £25

          Europe - £25

          Canada and the rest of the world £35

          * 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.

          Taxes and Customs fees

          • UK sales: Atom Packs is registered for VAT - this means that if you live in the UK, your price will include VAT at 20%. This will be automatically calculated at checkout.
          • Non-UK Sales: Each pack that we export out of the UK has the VAT value deducted - this is calculated automatically by your shipping and billing address at checkout. Look out for the exc VAT price listed on each product page

          Once your order leaves the UK and lands in the destination country, the destination country’s customs team will calculate the customs and duty owed by the recipient. Keep an eye out for contact from the postal service or UPS asking for funds before they release the package*. This will normally be a small duty charge and then your relevant sales tax (VAT equivalent) - It is your responsibility to inform yourself of these charges before purchasing, check online to find your country’s rate and what applies to you. A safe estimate would be roughly 25% of the final value of your order, including shipping.

          *Customs Fees USA: Good news for our US customers, the US currently has an $800 tariff free limit on imports - this means that all but the biggest orders see no customs fees on import to the US.

          We have tried our hardest to mitigate the cost to the consumer of shipping overseas but we cannot legally amend or alter the customs form to indicate a lower price, so please don’t ask us.

          Delivery and failed delivery: It is your responsibility to collect your delivery in a timely fashion, if an item is returned to us as undeliverable then we will have to charge you for re-delivery - keep an eye out for emails from us detailing information about your order so you are ready to receive it.

          Please make sure someone will be at the address to receive the order, our lead time is an estimate only and sometimes we may ship an item out sooner. We will gladly hold off on mailing an item if we know you won’t be in, so be sure to let us know if you are planning to be away from the address. Once the item is shipped, you can use the courier’s delivery portal to manage the delivery.

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