Outdoor Vitals CS40 Ultra Backpack vs Zpacks Nero Classic Backpack
Weight and specs compared for 2026 — and which one to choose.
40L ultralight backpack with carbon fiber frame stays. Weighs 27oz and supports up to 35 lbs with full functionality.
Full details →Ultralight frameless Dyneema Composite backpack, just 289g. Roll-top closure with mesh side pockets. Ideal for SUL hikers carrying under 10 lbs base weight.
Full details →HikeLoad is reader-supported. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you. Learn more.
Outdoor Vitals CS40 Ultra Backpack vs Zpacks Nero Classic Backpack: which should you buy?
If saving weight is your priority, the Zpacks Nero Classic Backpack wins — at 289 g it is 476 g (62%) lighter than the Outdoor Vitals CS40 Ultra Backpack (765 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.