ULA Circuit vs Zpacks Arc Haul Ultra 50L
Weight and specs compared for 2026 — and which one to choose.
Ultralight thru-hiking pack with carbon fiber frame and Dyneema Composite Hybrid fabric. Features roll-top closure and adjustable torso fit.
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ULA Circuit vs Zpacks Arc Haul Ultra 50L: which should you buy?
If saving weight is your priority, the Zpacks Arc Haul Ultra 50L wins — at 606 g it is 74 g (11%) lighter than the ULA Circuit (680 g). That said, the heavier option may justify the extra grams with more capacity, durability or comfort, so weigh the trade-off against how you'll use it.
See where both rank against everything else in this category on the lightest backpack page, or browse the full gear weight database.