I bought it to fit inside my memphis shade bullet fairing. It tucks in nice and snug over the headlight and in between the brackets. I have to pull it out of its spot to open the zipper. It holds a few things that I want to carry and not have my pockets full or hold inside my jacket. Hat fits in pretty good. Too small for an extra visor I think. Fits a water bottle. I haven't tried too many things yet. But, does what I need it to do.
This isn't the traditional leather tool bag, but "real world" everyday use requires a water repellent material like Cordura. This bag holds its shape and has ample room for rain pants, bungee net and disc rotor lock.