The box itself is great, and much bigger than my older boxes, however my helmet is quite large so there is no way this box would fit 2 of them. But it could probably fit two smaller full face helmets.

To attach the backrest you have to tape on a template, and drill two holes in the box, and the brake lights looked kinda complicated to install (for me at least).

The internal document holder

I’ve seen on forums and stuff that several people have had problems with this, the locking mechanism (see image above) kinda tricks you into believing that you are supposed to squeeze it someway, or even to remove the center pin.

The way you’re supposed to do this by the way is just to pull (using quite a bit of force) on the red plastic around the lock, to open it. Maybe I’ll put up a video when I get my new camera.