KS Ultralight KS27 vs. REI Co-op Trail Pack 25
Two carry-on travel backpacks, compared spec for spec.
KS Ultralight KS27
| Capacity | 27 L |
| Weight | 0.3 kg |
| Dimensions | 55×28×16 cm |
| Airline fit | 87% |
| Price | $130 |
Feature by feature
| KS Ultralight KS27 | Feature | REI Co-op Trail Pack 25 |
|---|---|---|
| Storage | ||
| 2 | Compression | 2 |
| None | Expanded Capacity | None |
| 0 | Opening | 0 |
| top | Passport | top |
| N | Passthrough | N |
| Carry | ||
| Y | Backpack | Y |
| removable | Hip Belt | removable |
| removable | Sternum Strap | Y |
| Inside | ||
| N | Laptop | N |
| 2 | Main Compartments | 3 |
| N | Organizer | N |
| Outside | ||
| × | Hard Shell | × |
| N | Rain-fly | Y |
| 2, side | Water Bottle Holder | 2, side |
| Y | Water Resistant | Y |
| Material | |
| X-pac VX 07 YKK "waterproof zip" | 210-denier ripstop nylon |
REI Co-op Trail Pack 25
| Capacity | 25 L |
| Weight | 0.8 kg |
| Dimensions | 46×33×20 cm |
| Airline fit | 94% |
| Price | $100 |
Key differences between the KS Ultralight KS27 and REI Co-op Trail Pack 25
- Sternum strap: Removable on the KS Ultralight KS27; Yes on the REI Co-op Trail Pack 25.
- Main compartments: 2 on the KS Ultralight KS27; 3 on the REI Co-op Trail Pack 25.
- Rain cover: No on the KS Ultralight KS27; Yes on the REI Co-op Trail Pack 25.
Both have: compression straps, passport pocket, backpack straps, hip belt, 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. 163 accept both. 1 accept only the KS Ultralight KS27, and 14 accept only the REI Co-op Trail Pack 25.
Only the KS Ultralight KS27 fits
Great Lakes Airlines.
Only the REI Co-op Trail Pack 25 fits
American Eagle, Belavia, easyJet, Etihad Airways, Liat Airlines, Oman Air, Qatar Airways, Ravn Alaska, Regional Express, Royal Jordanian, Scoot, Tiger Airways, Virgin Australia, WestJet.
KS Ultralight KS27 vs. REI Co-op Trail Pack 25: which should you pack?
The KS Ultralight KS27 carries 2L more than the REI Co-op Trail Pack 25 (27L vs. 25L), while the KS Ultralight KS27 is the lighter pack at 0.3kg (vs. 0.8kg). For carry-on flexibility, the REI Co-op Trail Pack 25 fits 94% of the airlines we track — the higher of the two. If you prioritise packing volume, choose the KS Ultralight KS27; if you want to travel lighter, the KS Ultralight KS27 is the better call.