The way I picture it, when the designers sat down to create the Momentum, they referred to a commuter’s wish-list of features and started figuring out what they could incorporate and what they would need to get rid of. Fortunately, I don’t think there were too many things crossed out. I was sent the 26 liter pack by Osprey to try out. It’s the smaller of the two packs, weighing just a hair over a pound. For my 5′8″ frame, it was the perfect size. To be honest, I used to be into carrying huge packs just in case I needed the volume. The reality is I don’t really need a large pack.