Bonfus Aerus 55L
Ultralight Pack
~$389

Bonfus

Bonfus Aerus 55L

Bonfus gives the Aerus 55L a ventilated back: a tensioned mesh panel stands off a curved 7075 aluminium frame braced with four carbon-fibre cross elements, the trampoline layout normally found on much heavier packs. Total volume is 55 L (47 L internal plus 8 L external) and the medium weighs 795 g in Ultra 200X. It is rated to 33 lb.

Approx. price
~$389
Capacity
55 L
Weight
1.75 lbs
Best For
Hot-weather thru-hikers who want an airflow back without leaving the sub-2 lb class
Type
Ultralight Pack
Frame Type
Internal Frame
Capacity
55 L
Weight
1.75 lbs
Max Recommended Load
33 lbs (15 kg)
Torso Fit
Sized S to 18 in / M to 19.5 in / L to 22 in; hipbelt short 29.5-39 in or M/L 33-43 in
Material
Ultra 200X with taped seams (UltraGrid option)
Back Panel
Tensioned mesh suspended off a curved 7075 aluminium frame with four carbon-fibre cross elements
Warranty
Bonfus warranty: 2 years from receipt against material defects and workmanship failure; original owner, excludes normal wear and tear
Raincover Included
No
Fits BV500 Bear Canister
No

Features

Ventilated Back

Pros

  • ✓One of very few ultralight packs with a true suspended-mesh ventilated back.
  • ✓795 g in the medium is light for a framed 55 L with that suspension.
  • ✓Ultra 200X body with taped seams sheds water well.
  • ✓Three torso sizes and two hipbelt lengths.
  • ✓Bonfus publishes a clear 33 lb load rating.

Cons

  • ✗$389 is among the highest prices for a 55 L ultralight pack.
  • ✗Hipbelt pockets are a $27-each extra.
  • ✗33 lb is a lower ceiling than some framed 55 L rivals that carry 35-40 lb.
  • ✗A trampoline back pushes the load away from the spine, which can feel less stable than a contact back.
  • ✗No stated hydration sleeve or bear-canister fit.

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Capacity

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Frame

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Weight

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Capacity

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Frame

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Hyperlite Mountain Gear

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Weight

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Capacity

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Frame

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Capacity

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Frame

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Weight

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Capacity

68 L

Frame

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Weight

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Capacity

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Frame

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