Alpha One-Niner SERT, PENUMBRA 2.0 Backpack vs. Aer City Pack Pro 2
Two carry-on travel backpacks, compared spec for spec.
Alpha One-Niner SERT, PENUMBRA 2.0 Backpack
| Capacity | 21 L |
| Weight | 1.5 kg |
| Dimensions | 47×30×14 cm |
| Airline fit | 93% |
| Price | $255 |
Feature by feature
| Alpha One-Niner SERT, PENUMBRA 2.0 Backpack | Feature | Aer City Pack Pro 2 |
|---|---|---|
| Storage | ||
| 2 | Compression | N |
| None | Expanded Capacity | None |
| 1 | Opening | 1 |
| front | Passport | top, side |
| Y | Passthrough | Y |
| Carry | ||
| Y | Backpack | Y |
| optional | Hip Belt | N |
| removable | Sternum Strap | removable |
| Inside | ||
| 16in | Laptop | 16in |
| 5 | Main Compartments | 4 |
| Y | Organizer | Y |
| Outside | ||
| × | Hard Shell | × |
| N | Rain-fly | N |
| 2, side | Water Bottle Holder | 2, side |
| Y | Water Resistant | Y |
| Material | |
| Available in: X-Pac X42, 500D, 630D HD | 1680D CORDURA® ballistic nylon |
Key differences between the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack and Aer City Pack Pro 2
- Compression straps: 2 on the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack; No on the Aer City Pack Pro 2.
- Passport pocket: Front on the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack; Top, side on the Aer City Pack Pro 2.
- Hip belt: Optional on the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack; No on the Aer City Pack Pro 2.
- Main compartments: 5 on the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack; 4 on the Aer City Pack Pro 2.
Both have: luggage passthrough, backpack straps, sternum strap, laptop sleeve, built-in organizer, water bottle pockets, water resistant.
Which airlines take each bag as a carry-on
We checked both bags against the carry-on size limits of 189 airlines. 174 accept both. 1 accept only the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack, and 3 accept only the Aer City Pack Pro 2.
Only the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack fits
Air Niugini.
Only the Aer City Pack Pro 2 fits
American Eagle, easyJet, Ravn Alaska.
Alpha One-Niner SERT, PENUMBRA 2.0 Backpack vs. Aer City Pack Pro 2: which should you pack?
The Aer City Pack Pro 2 carries 3L more than the Alpha One-Niner SERT, PENUMBRA 2.0 Backpack (21L vs. 24L), while the Aer City Pack Pro 2 is the lighter pack at 1.3kg (vs. 1.5kg). For carry-on flexibility, the Aer City Pack Pro 2 fits 94% of the airlines we track — the higher of the two. If you prioritise packing volume, choose the Aer City Pack Pro 2; if you want to travel lighter, the Aer City Pack Pro 2 is the better call.