Bellroy Apex Backpack vs. Boundary Supply Rennen X-Pac Daypack

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

Bellroy Apex Backpack

Front facing view of the Bellroy Apex Backpack
Capacity26 L
Weight1.4 kg
Dimensions55×33×20 cm
Airline fit86%
Price$449

Feature by feature

Bellroy Apex BackpackFeatureBoundary Supply Rennen X-Pac Daypack
Storage
N Compression N
None Expanded Capacity None
0 Opening 4
N Passport N
N Passthrough N
Carry
Y Backpack Y
N Hip Belt N
removable Sternum Strap N
Inside
15in Laptop 15in
1 Main Compartments 1
N Organizer N
Outside
× Hard Shell ×
N Rain-fly N
1 Water Bottle Holder 1
Y Water Resistant Y
Material
Recycled Baida Nylon and premium, environmentally certified leatherCustom VX21 X-Pac material

Boundary Supply Rennen X-Pac Daypack

Front facing view of the Boundary Supply Rennen X-Pac Daypack
Capacity22 L
Weight0.9 kg
Dimensions46×28×18 cm
Airline fit95%
Price$170

Key differences between the Bellroy Apex Backpack and Boundary Supply Rennen X-Pac Daypack

Both have: backpack straps, laptop sleeve, 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. 0 accept only the Bellroy Apex Backpack, and 16 accept only the Boundary Supply Rennen X-Pac Daypack.

Only the Boundary Supply Rennen X-Pac Daypack fits

Air Niugini, American Eagle, Belavia, easyJet, Etihad Airways, Great Lakes Airlines, Liat Airlines, Oman Air, Qatar Airways, Ravn Alaska, Regional Express, Royal Jordanian, Scoot, Tiger Airways, Virgin Australia, WestJet.

Bellroy Apex Backpack vs. Boundary Supply Rennen X-Pac Daypack: which should you pack?

The Bellroy Apex Backpack carries 4L more than the Boundary Supply Rennen X-Pac Daypack (26L vs. 22L), while the Boundary Supply Rennen X-Pac Daypack is the lighter pack at 0.9kg (vs. 1.4kg). For carry-on flexibility, the Boundary Supply Rennen X-Pac Daypack fits 95% of the airlines we track — the higher of the two. If you prioritise packing volume, choose the Bellroy Apex Backpack; if you want to travel lighter, the Boundary Supply Rennen X-Pac Daypack is the better call.