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Hyperlite Mountain Gear Unbound 40 vs Zpacks Nero Classic Ultra Backpack

Weight and specs compared for 2026 — and which one to choose.

Zpacks Nero Classic Ultra Backpack is the lighter option — 541 g lighter than the Hyperlite Mountain Gear Unbound 40 (65% less weight). If grams matter to you, that is the one to beat.
Spec Hyperlite Mountain Gear Unbound 40 Zpacks Nero Classic Ultra Backpack
Weight 830 g · 0.830 kg · 1.83 lb 289 g · 0.289 kg · 0.64 lb
Brand Hyperlite Mountain Gear Zpacks
Category Backpack Backpack
Hyperlite Mountain Gear Unbound 40
830 g

40L Dyneema Composite Hybrid pack with internal frame and waterproof roll-top closure. Built for alpine and storm-prone conditions.

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Zpacks Nero Classic Ultra Backpack
289 g

Frameless ultralight backpack made from Dyneema Composite Fabric. Minimalist design for SUL hikers. Top-loading with roll-top closure.

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Hyperlite Mountain Gear Unbound 40 vs Zpacks Nero Classic Ultra Backpack: which should you buy?

If saving weight is your priority, the Zpacks Nero Classic Ultra Backpack wins — at 289 g it is 541 g (65%) lighter than the Hyperlite Mountain Gear Unbound 40 (830 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.

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