Lowepro Flipside Trek BP 450 AW vs Tortuga Expandable Backpack
The Lowepro Flipside Trek BP 450 AW is 27L and 1.69kg3.7lb; the Tortuga Expandable Backpack is 27L and 1.6kg3.5lb. The Tortuga Expandable Backpack is 0.09kg0.2lb lighter. The Tortuga Expandable Backpack costs $69 less. The Lowepro Flipside Trek BP 450 AW fits the carry-on limit of 14 of 36 major airlines and the Tortuga Expandable Backpack fits 36; under the seat, 0 and 0 of 26.
| Spec | Lowepro Flipside Trek BP 450 AW | Tortuga Expandable Backpack |
|---|---|---|
| Price | $319 | $250Best |
| Volume | 27L | 27L |
| Expands to | n/a | 32.5L |
| Weight | 1.69kg3.7lb | 1.6kg3.5lbBest |
| Carry-on compliance | 39% | 100%Best |
| Personal-item compliance | 0% | 0% |
| Dimensions | 54×31×24cm21.5×12×9.5in | 49×32×18cm19.5×12.5×7in |
| Laptop | no laptop sleeve | 16" |
| Compartments | 2 | n/a |
| Bottle pockets | n/a | 1 |
| Compression straps | n/a | 0 |
| Opening | Panel access, body-side + top | Panel access, front-loading |
| Warranty | n/a | Lifetime |
| Torso length | n/a | 43 to 48cm (17 to 19in) |
| Fit | n/a | Unisex |
| Organizer | No | Yes |
| Shoe compartment | No | No |
| Hydration sleeve | No | No |
| Frame sheet | No | No |
| Water-resistant | No | No |
| Rain cover | Yes | No |
| MOLLE | No | No |
| Hip belt | No | Removable |
| Sternum strap | No | Yes |
| Load lifters | No | Yes |
| Shoulder strap | No | No |
| Luggage pass-through | No | Yes |
| Camera compartment | Yes | No |
| Material | nylon | 630D CORDURA re/cor RN6 nylon |
| Last checked | 2026-09 | 2026-09 |
Where their airline fit differs
| Airline | Limit | Lowepro Flipside Trek BP 450 AW | Tortuga Expandable Backpack |
|---|---|---|---|
| Air Arabia | Carry-on | Too big | Fits |
| Air Canada | Carry-on | Too big | Fits |
| Air India | Carry-on | Too big | Fits |
| AirAsia | Carry-on | Too big | Fits |
| Alaska Airlines | Carry-on | Too big | Fits |
| American Airlines | Carry-on | Too big | Fits |
| Cebu Pacific | Carry-on | Too big | Fits |
| Delta Air Lines | Carry-on | Too big | Fits |
| Emirates | Carry-on | Too big | Fits |
| JetBlue Airways | Carry-on | Too big | Fits |
| Lufthansa | Carry-on | Too big | Fits |
| Norwegian Air Shuttle | Carry-on | Too big | Fits |
| Qantas | Carry-on | Too big | Fits |
| Qatar Airways | Carry-on | Too big | Fits |
| Ryanair | Carry-on | Too big | Fits |
| SAS | Carry-on | Too big | Fits |
| Turkish Airlines | Carry-on | Too big | Fits |
| United Airlines | Carry-on | Too big | Fits |
| Vietjet Air | Carry-on | Too big | Fits |
| Vueling | Carry-on | Too big | Fits |
| WestJet | Carry-on | Too big | Fits |
| Wizz Air | Carry-on | Too big | Fits |
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Specs come from each brand's own product page. Fit uses listed dimensions in any orientation. How we score carry-on fit.