Black Ember V4 Pack
The main zipper on the 33-liter V4 (from $155) splays completely open. Inside, it has modular cubes that snap in via magnetic locks. Each cube can be organized to hold various types of gear, like your cameras, work kit, and extra clothes. Packed full, the bag is carry-on-compliant, and it also comes with a detachable laptop sleeve that's TSA-friendly.