---
url: "https://onebag.travel/compare/ayd517mvmi/alpha-one-niner-sert-penumbra-2-0-backpack/rjqv8c8bu9/travel-pack-3/"
title: "Alpha One-Niner SERT, PENUMBRA 2.0 Backpack vs Travel Pack 3"
description: "Alpha One-Niner SERT, PENUMBRA 2.0 Backpack vs Travel Pack 3: capacity, weight, dimensions and how many airlines accept each as a carry-on, side by side."
source: "https://onebag.travel/compare/ayd517mvmi/alpha-one-niner-sert-penumbra-2-0-backpack/rjqv8c8bu9/travel-pack-3/"
---
1.  [Home](https://onebag.travel/)
2.  [Carry-On Travel Backpacks](https://onebag.travel/carryons/)
3.  Alpha One-Niner SERT, PENUMBRA 2.0 Backpack vs. Travel Pack 3

# Alpha One-Niner SERT, PENUMBRA 2.0 Backpack vs. Travel Pack 3

Two carry-on travel backpacks, compared spec for spec.

## [Alpha One-Niner SERT, PENUMBRA 2.0 Backpack](https://onebag.travel/carryon/ayd517mvmi/alpha-one-niner-sert-penumbra-2-0-backpack/)

by [Alpha One-Niner](https://onebag.travel/carryons/?brands=Alpha One-Niner)

![Front facing view of the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack](https://res.cloudinary.com/obt/image/upload/c_fill,w_400/v1788990332/carryons/alpha-one-niner-sert-penumbra-2-0-backpack-ayd517mvmi.webp)

<table class="table table-sm cmp-spec mt-2"><tbody><tr><td>Capacity</td><td>21 L</td></tr><tr><td>Weight</td><td>1.5 kg</td></tr><tr><td>Dimensions</td><td>47×30×14 cm</td></tr><tr><td>Airline fit</td><td>93%</td></tr><tr><td>Price</td><td>$255</td></tr></tbody></table>

## Feature by feature

| Alpha One-Niner SERT, PENUMBRA 2.0 Backpack | Feature | Travel Pack 3 |
| --- | --- | --- |
| Storage |
| 2 | Compression | Y |
| None | Expanded Capacity | None |
| 1 | Opening | 1 |
| front | Passport | top, side |
| Y | Passthrough | Y |
| Carry |
| Y | Backpack | Y |
| optional | Hip Belt | optional |
| removable | Sternum Strap | removable |
| Inside |
| 16in | Laptop | 16in |
| 5 | Main Compartments | 5 |
| Y | Organizer | Y |
| Outside |
| × | Hard Shell | × |
| N | Rain-fly | N |
| 2, side | Water Bottle Holder | 1, side |
| Y | Water Resistant | Y |

<table class="cmp-material"><tbody><tr><td colspan="2">Material</td></tr><tr><td>Available in: X-Pac X42, 500D, 630D HD</td><td>1680D Cordura® ballistic nylon</td></tr></tbody></table>

## [Travel Pack 3](https://onebag.travel/carryon/rjqv8c8bu9/travel-pack-3/)

by [Aer](https://onebag.travel/carryons/?brands=Aer)

<table class="table table-sm cmp-spec mt-2"><tbody><tr><td>Capacity</td><td>35 L</td></tr><tr><td>Weight</td><td>1.9 kg</td></tr><tr><td>Dimensions</td><td>55×33×23 cm</td></tr><tr><td>Airline fit</td><td>68%</td></tr><tr><td>Price</td><td>$249</td></tr></tbody></table>

## Key differences between the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack and Travel Pack 3

-   **Compression straps:** 2 on the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack; Yes on the Travel Pack 3.
-   **Passport pocket:** Front on the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack; Top, side on the Travel Pack 3.
-   **Water bottle pockets:** 2, side on the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack; 1, side on the Travel Pack 3.

Both have: luggage passthrough, backpack straps, hip belt, sternum strap, laptop sleeve, built-in organizer, water resistant.

## Which airlines take each bag as a carry-on

We checked both bags against the carry-on size limits of 189 airlines. 129 accept both. 46 accept only the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack, and 0 accept only the Travel Pack 3.

### Only the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack fits

Air Baltic, Air China, Air Malta, Air Niugini, Air Serbia, Air Seychelles, Asiana Airlines, ATA Airlines, Belavia, Blue Air, Bulgaria Air, China Eastern, Emirates Airlines, Enter Air, Etihad Airways, flybe, Icelandair, InselAir, Juneyao Airlines, Liat Airlines, Luxair, Meridiana Fly, Nordwind Airlines, Oman Air, Pakistan International, Qatar Airways, Regional Express, Royal Brunei Airlines, Royal Jordanian, Ryanair, S7, Scoot, Shandong Airlines, Shenzhen Airlines, Sun Express, TAP Air Portugal, TAROM, Tianjin Airlines (A320 & E190), Tiger Airways, TUI, Ukraine International, VIM Airlines (Closed), Virgin Australia, Volotea, WestJet, Xiamen.

## Alpha One-Niner SERT, PENUMBRA 2.0 Backpack vs. Travel Pack 3: which should you pack?

The **Travel Pack 3** carries 14L more than the **Alpha One-Niner SERT, PENUMBRA 2.0 Backpack** (21L vs. 35L), while the **Alpha One-Niner SERT, PENUMBRA 2.0 Backpack** is the lighter pack at 1.5kg (vs. 1.9kg). For carry-on flexibility, the **Alpha One-Niner SERT, PENUMBRA 2.0 Backpack** fits 93% of the airlines we track — the higher of the two. If you prioritise packing volume, choose the Travel Pack 3; if you want to travel lighter, the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack is the better call.