Hyperlite Mountain Gear Unbound 40L vs Six Moon Designs Swift X
Weight and specs compared for 2026 — and which one to choose.
Ultralight 40L pack in woven Dyneema Composite Fabric with internal frame stays and hipbelt. Ideal for fast alpine and thru-hiking missions.
Full details →Highly configurable 50L ultralight pack with removable stay, hip belt and vest harness options to dial in fit and weight.
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Hyperlite Mountain Gear Unbound 40L vs Six Moon Designs Swift X: which should you buy?
If saving weight is your priority, the Six Moon Designs Swift X wins — at 765 g it is 88 g (10%) lighter than the Hyperlite Mountain Gear Unbound 40L (853 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.