ULA Equipment ULA Circuit Backpack vs Deuter Aircontact Core 45+10 SL

Editorial Team
Last modified at July 22, 2026
Choosing the right backpacking backpack can significantly enhance your outdoor experience. The ULA Circuit Backpack and the Deuter Aircontact Core 45+10 SL are both excellent choices, but they cater to slightly different needs. The ULA Circuit is renowned for its exceptional load transfer and organization, making it a favorite among those who need to carry heavy loads comfortably. On the other hand, the Deuter Aircontact Core stands out with its superior ventilation and adjustable fit, ideal for those who prioritize breathability and a customized fit.

Why You Can Trust Us

  • Side-by-side analysis based on real user feedback
  • Unbiased comparisons, not influenced by partnerships
  • Updated as new data becomes available

We may earn from affiliate links at no extra cost to you.

ULA Equipment ULA Circuit BackpackDeuter Aircontact Core 45+10 SL
ULA Circuit Backpack
Deuter Aircontact Core 45+10 SL
Capacity

68 L total: 39.3 L main body; 6.6 L front; 6.6 L each side; 8.2 L collar; 1.5 L each hipbelt pocket

45+10 L (55 L expanded)

Weight

2 lb 6.5 oz (38.5 oz)

4 lb 12.5 oz (2,170 g)

Torso Adjustability

SMALL: 15–18 in
MEDIUM: 18–21 in
LARGE: 21–24 in
X-LARGE: 24+ in

14–22 in

Hip Belt Size Range

X-SMALL: 26–30 in
SMALL: 30–34 in
MEDIUM: 34–38 in
LARGE: 38–42 in
X-LARGE: 42–47 in
XX-LARGE: 47+ in

Not specified by current US manufacturer or retailer

Hydration Compatibility

Yes; hydration port, optional sleeve

Yes; up to 3 L reservoir

Warranty

Lifetime (original owner, defects in materials and workmanship)

deuter USA lifetime warranty

Trekking Pole Attachment

Yes (Ice Axe/Trekking Pole Loops)

Yes

Rain Cover Compatibility

Compatible; sold separately

Compatible; not included on current US model

Side Pockets

Yes (each accommodates two 1-Liter bottles)

Yes

Hip Pockets

Yes (Dual Hipbelt Pockets)

Yes

Sternum Strap

Yes (Removable & Height Adjustable)

Yes (2-way adjustable)

Load Lifters

Yes (adjustable)

Yes

Sleeping Bag Compartment

No separate compartment; roll-top main body

Yes (separate bottom compartment)

Comfort

ULA Circuit Backpack

4.2/ 5.0

Deuter Aircontact Core 45+10 SL

4.4/ 5.0

Comfort is crucial for backpacking backpacks as it directly impacts your endurance and enjoyment on long trails. A comfortable backpack ensures that you can carry your load without straining your back and shoulders, making your journey more pleasant. The Deuter Aircontact Core 45+10 SL excels in this category with a score of 4.4/5, praised for its comfortable fit, flexible hip belt, and lumbar support. Buyers highlight its ability to distribute weight effectively to the hips, reducing shoulder strain. The ULA Circuit Backpack, while still comfortable with a score of 4.2/5, has some complaints about back sweating and mesh comfort. Therefore, if comfort is your top priority, the Deuter Aircontact Core is the better choice.

Fit

ULA Circuit Backpack

4.7/ 5.0

Deuter Aircontact Core 45+10 SL

4.6/ 5.0

A good fit ensures that the backpack sits correctly on your body, distributing weight evenly and reducing the risk of discomfort or injury. Both the ULA Circuit Backpack and the Deuter Aircontact Core 45+10 SL score highly in this category, with the ULA Circuit slightly ahead at 4.7/5 compared to the Deuter's 4.6/5. The ULA Circuit is praised for its adjustable shoulder straps and height-adjustable hip belt, making it versatile for various body types. The Deuter Aircontact Core is also highly adjustable, with pivoting hip and shoulder strap attachments that cater well to shorter frames. Given the minimal difference in scores and the high adjustability of both packs, this category is a tie.

Load Transfer

ULA Circuit Backpack

4.7/ 5.0

Deuter Aircontact Core 45+10 SL

4.4/ 5.0

Effective load transfer is essential for reducing strain on your back and shoulders, especially during long hikes with heavy loads. The ULA Circuit Backpack excels in this category with a score of 4.7/5, thanks to its four-point contact hip belt system and load lifters that spread weight effectively. Buyers consistently praise its ability to carry heavy loads comfortably. The Deuter Aircontact Core, with a score of 4.4/5, also performs well but is slightly less effective in distributing weight to the hips. If carrying heavy loads is a priority, the ULA Circuit is the clear winner.

Ventilation

ULA Circuit Backpack

2.8/ 5.0

Deuter Aircontact Core 45+10 SL

4.4/ 5.0

Proper ventilation helps keep your back cool and dry, enhancing comfort during long hikes, especially in warm weather. The Deuter Aircontact Core 45+10 SL significantly outperforms the ULA Circuit Backpack in this category, with a score of 4.4/5 compared to the ULA's 2.8/5. The Deuter is praised for its three-dimensional air spacer mesh and wide ventilation channel, which keep the back from getting too sweaty. The ULA Circuit, however, has complaints about back sweating and less effective mesh. For better ventilation, the Deuter Aircontact Core is the superior choice.

Organization

ULA Circuit Backpack

4.7/ 5.0

Deuter Aircontact Core 45+10 SL

4.3/ 5.0

Good organization in a backpack allows for easy access to your gear and helps keep your belongings well-arranged. The ULA Circuit Backpack scores higher in this category with a 4.7/5, praised for its removable straps, cinchable side pockets, and roll-top closure that make packing and accessing gear straightforward. The Deuter Aircontact Core, with a score of 4.3/5, also offers good organization with multiple pockets and attachment loops, but it falls slightly short compared to the ULA Circuit. If organization is a key factor for you, the ULA Circuit is the better option.

Accessibility

ULA Circuit Backpack

4.2/ 5.0

Deuter Aircontact Core 45+10 SL

4.2/ 5.0

Accessibility refers to how easily you can reach your gear without having to dig through your pack. Both the ULA Circuit Backpack and the Deuter Aircontact Core 45+10 SL score equally in this category with a 4.2/5. The ULA Circuit is praised for its side pouches and pockets, while the Deuter Aircontact Core is noted for its easily adjustable harness and cinch straps. Given the similar scores and positive feedback for both, this category is a tie.

Trust & Transparency

  • Data-driven rankings from real user reviews
  • Affiliate partnerships don't influence our methodology

We may earn commission from links.

Conclusion & Final Verdict:

In conclusion, the ULA Circuit Backpack and the Deuter Aircontact Core 45+10 SL each have their strengths. The ULA Circuit is the better choice for those who prioritize load transfer, organization, and lighter weight, making it ideal for long trails with heavy loads. On the other hand, the Deuter Aircontact Core excels in ventilation and fit adjustability, making it a great option for those who need better breathability and a more customized fit. Ultimately, your choice will depend on your specific needs and preferences.

See All Comparisons

Related Comparisons