STM Prime vs. Waymark Dark Sky
Two carry-on travel backpacks, compared spec for spec.
STM Prime
| Capacity | 15 L |
| Weight | 0.7 kg |
| Dimensions | 42×26×13 cm |
| Airline fit | 96% |
| Price | $80 |
Feature by feature
| STM Prime | Feature | Waymark Dark Sky |
|---|---|---|
| Storage | ||
| N | Compression | N |
| None | Expanded Capacity | None |
| 0 | Opening | 0 |
| top | Passport | N |
| N | Passthrough | N |
| Carry | ||
| Y | Backpack | Y |
| N | Hip Belt | N |
| Y | Sternum Strap | Y |
| Inside | ||
| 13in | Laptop | N |
| 2 | Main Compartments | 2 |
| N | Organizer | N |
| Outside | ||
| × | Hard Shell | × |
| N | Rain-fly | N |
| 2, side | Water Bottle Holder | 2, side |
| Y | Water Resistant | Y |
| Material | |
| Polyester | Recycled RBC350 Ripstop Polyester, RBC600, RBC200 fabrics |
Waymark Dark Sky
| Capacity | 16 L |
| Weight | 0.4 kg |
| Dimensions | 41×27×14 cm |
| Airline fit | 96% |
| Price | $115 |
Key differences between the STM Prime and Waymark Dark Sky
- Passport pocket: Top on the STM Prime; No on the Waymark Dark Sky.
- Laptop sleeve: 13in on the STM Prime; No on the Waymark Dark Sky.
Both have: backpack straps, sternum strap, 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. 181 accept both. Every airline that takes one takes the other.
STM Prime vs. Waymark Dark Sky: which should you pack?
The Waymark Dark Sky carries 1L more than the STM Prime (15L vs. 16L), while the Waymark Dark Sky is the lighter pack at 0.4kg (vs. 0.7kg). For carry-on flexibility, the STM Prime fits 96% of the airlines we track — the higher of the two. If you prioritise packing volume, choose the Waymark Dark Sky; if you want to travel lighter, the Waymark Dark Sky is the better call.